Cyclic Wetting and Drying and Chloride · between saturated and partially saninited States, as they...

Cyclic Wetting and Drying and its Effects on Chloride Ingress in Concrete

Katherine Hong

A thesis submitted in confomity with the requirements for the degree of Master of Applied Science Graduate Department of Civil Enginee~g

University of Toronto

Q Copyright by Katherine Hong 1998

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Cyclic Wettiag and Drying and its Effecrs on Chloride Ingres5 in Concrete, Katherine Hong, U S c . 1 998, Department of Civil Engineering, University of Toronto

Abstract

Aimost al1 forms of deterioration in reidorced concrete involve ingress of deleterious fluids

through the pore structure of the concrete. In particular the ingress of chlorides is a major cause

of early deterioration of reidorced concrete structures due to subsequent corrosion.

in saturated concretes, fluids will enter through diffusion whereas partiaily saturated concretes,

fluids will be absorbed by capillary suction. In reality most concretes are in a continual flux

between saturated and partially saninited States, as they undergo continuous cycles of wetting and

drymg. The primary focus of this study is to examine the effects of cyclic wetting and drymg

with sodium chloride solution. Chloride profiles of samples exposed to various numbers of

cycles, and lengths of cycles were determined. From these profiles, the rate and depths of

chlofide ingress were calculated and compared for two mixtures of concrete containing slag

and/or silica fume with a 0.4 w/c, and one with a 0.3 w/c.

Acknowledgmen ts

I would like to thank my supervisor Professor R.D. Hooton, for giving me the privilege to

experience and l e m about the area of research, in particular concrete materials research. The

opportunity helped me to understand and redize that the wheeis of discovery grind at a slow and

heavy cost. This has given me a greater appreciation of the compiexity of our worid.

I would also like to thank the lab technicians, my fellow students and labmates for their vital help

in performing ail the lab work. Not ody were they fkiendly and helpful, but they were a source

of encouragement and insight that was needed for the day - to - &y grind. I would especially like

to thank Ursula for aiways being helpful, Maura for your diligence, Melissa for sharing your

knowledge, and Stepanka and Diane for al1 your support.

As well, I would like to thank the Natural Sciences and Engineering Research Council and the

Ontario Centre of Materials Research for the fünding they provided throughout this project.

Finally, above al1 else 1 give thanks to the LORD, whom without I could never have finished this

project. For during those long days and nights of work when I was discouraged, He gave me the

strength to keep trying to do my best, and heiped me to realize 1 was never called to be the best.

Table of Contents

.. Abstract ...................................................................................... ... 11 ... ................................... ...........................*.*...*.....*.... Acknowledgments ... III

.................................................................................... Table of Contents iv

.................................................................................... List of Tables vi . . ..................................................................................... List of Figures v11

1.0 Introduction ................................................................................ 1.1 Background 1

1.2 Chloride ingress ...................................................................... -. 3

1 -3 Repair and Maintenance ............................................................. 7 - 1.4 The Need for Service Life Modeling .................................................... 3 1.5 CyclicWettingandDrying ............................................................. 3 1 -6 Objective and Scope of Research .................................................... 4

2.0 Literature Review 2.1 Cyclic Wetting and Drying ............................................................. 5

2.1.1 Concrete Drying .............................................................. 6 ............................................................. 2.1.2 Concrete Wetting 7

............................................................................... 2.2 Fluid ingress 7 2.3 D i h i o n ............................................................................ 9 2.4 Sorptivity (Rate of Absorption) ................................................ I l

3.0 Experimental Method 3.1 Overview .............................................................................. 15 3.2 Materials .......................................................................... 15

............................................................ 3.2.1 Method of Mwng 16 .............................................................................. 3.2.2 Curing 18

............................................................ 3.3 Cyclic Wetting and Drying 18

............................................................ 3.3.1 Sample Identification 19

............................................................ 3.3.2 Specimen Preparation 20 3.4 Diffbion .............................................................................. 21

..................................................................... 3 -5 Chloride Analysis 22 3.5.1 Grinding ................................................................... _- 77

3.5.2 Nitric Acid Digestion ............................................................ 24 3.5.3 Titration .................................................................. 25

..................................................................... 3.6 Sorptivity Testhg 26 .............................................................................. 3.7 Absorption 27

3.8 Compression Strength Testing ........................... ., ..................... 28

4.0 Results and Discussion .............................................................................. 4.1 Overview 29

..................................................................... 4.2 Material Properties 29 ............................................................ 4.3 Cyclic Wetting and Drying 30

4.3.1 Mix1 .............................................................................. 32 4.3.2 Mix 2 .............................................................................. 33 4.3.3 Mix 3 .............................................................................. 35 4.3.4 Dryhg Period for High Quality Concretes ................................. 37

4.4 CycIic Wetting and Drying with Distilled Water ................................. 39 .............................................................................. 4.5 Diffbsion 42

4.5.1 D i h i o n with Washout ................................................... 45 .............................................................................. 4.6 Sorptivity 49

4.7 Predicting the Rate of Chioride Ingress ......................................... 50

5.0 ConcIusious and Recommendations ..................................... . 5.1 Conclusions ... 53

..................................................................... 5.2 Recornmendations 54

...................................................................................... 6.0 References 55

Appendix A . General Data Appendix B . Test Program Appendix C . Chloride Profiles Appendix D . Sorptivity Data

List of Tables

Table 3.1 TabIe 3.2 Table 3.3 Table 4.1 Table 4.2 Table 4.3 Table 4.4 Table 4.5 Table 4.6 Table 4.7 Table 4.8 Table 4.9 Table 4.1 O Table 4.1 1

Mix Designs ........................................................................... 16 Raw Materials ........................................................................... 16 Mixing Sequence ............................................................. 17

................... Materid Properties ,.., ............................................ 29 ....... Absorption. Bulk Specific Gravity. and Volume of Permeable Pores 30

Mix 1 : Chloride Profile Characteristics ......................................... 33 Mix 2: Chloride Profile Characteristics ....................................... 35 Mix 3: Chloride Profile Characteristics ......................................... 37 Mass of Chiorides Released ........................................................ 42

..................... ................................. Diffusion Characteristics ... 45 D i f i i o n Characteristics for Washout Series ........................................ 48

.................... ..................................... Mass of Chlorides Released ., 49 Sorptivity Results .................................................................... 50 Predicted Number of Cycles to Reach a Chloride Content 0.1 % at 10 mm ..... 52

List of Figures

Figure 2.1 Figure 3.1 Figure 3.2 Figure 3.3 Figure 4.1 Figure 4.2 Figure 4.3 Figure 4.4 Figure 4.5 Figure 4.6 Figure 4.7 Figure 4.8 Figure 4.9 Figure 4.10 Figure 4.1 1 Figure 4.12 Figure 4.13 Figure 4.14 Figure 4.15 Figure 4.16 Figure 4.17 Figure 4.18 Figure 4.19 Figure 4.20 Figure 4.2 1 Figure 4.22

Sorptivity Test ......................................................................... 12 Tirneline for C yclic Testing ......................................................... 20 T ie l ine for Diffusion Testing .................................................. 22

....................... Prepared Sample for Gtinding ....................... .., 23 MV< 1 Chloride Profiles for One-&y Cycles ......................................... 32 Mix 1 Chloride Profiles for Three-&y Cycles ................................ 32

......................................... Mix 2 Chloride Pronles for One-&y Cycles 34 Mix 2 Chioride Profiles for Three-day Cycles ................................ 34

....................................... Mix 3 Chloride Profiles for One-day Cycles 35 Mix 3 Chlonde Rofiles for Three-day Cycles ................................ 36

................................ Mix 1 Sorption Coefficient vs Number of Cycles 37

................................ Mix 2 Sorption Coefficient vs Number of Cycles 38

................................ Mix 3 Sorption Coefficient vs Number of Cycles 38 ....................... MU( 1 - Chloride Profiles for Cycles with Distiiled Water 39 ....................... Mix 2 - Chlonde Profiles for Cycles with Distilled Water 41 ....................... MDc 3 - Chloride Profiles for Cycles with Distilled Water 41

Mix 1 Diffusion Prolles ........................................................... 43 ....................... Mix 2 D i h i o n Profiles ................................... 43

Mix 3 Diffusion Profiles ........................................................ 44 Mix 1 D i h i o n Profiles with Washout Period ................................ 46 Mix 2 Diffusion Profiles with Washout Period ................................ 47 Mix 3 D i h i o n Profiles with Washout Period ................................ 47 Chlodes Released During Washout .................................................. 48 Mix 1 Depth vs Square Root of the Number of Cycles ....................... 50 Mix 2 Depth vs Square Root of the Number of Cycles ....................... 51 Mix 3 Depth vs Square Root of the Number of Cycles ....................... 51

vii

1.0 Introduction

1.1 Background

Concrete is the most widely used construction material in the world. h fact for every person

alive today, one ton of concrete is placed aonually [Mailvaganan, 19921. It is a strong and

durable matenal that is versatile, and economical [Kosmatka et al, 19951. One of the properties

of concrete is good compressive strength, although it is weak in tension. To compensate for this

weakness, reinforcing steel bars are used in tension zones of a structure, forming reinforced

concrete (RC) structures, such as bridges, and high rise buildings.

RC structures for the most part are very durable. The hi& allcaiinity of the concrete, promotes the

formation of a protective coating around the reinforcement bars that essentially passivates the

steel fiom corrosion, and possible deterioration. However, over t h e and exposure to various

harsh environments, many RC structures begin to degenerate. Some causes of deterioration are:

alkali silica reaction (ASR), corrosion of the rebar due to chlorides or carbonation, sulphate

attack, acid attack, leaching, and &eeze and thaw damage [Hooton, 19951.

Chloride-induced corrosion is one of the most dominate type of detenoration, as NaCl is

commonly used for roadhighway de-icing in Canada. As a result, during the winter the roads are

regularly receiving dosages of salt, which melts the snow and ice, to form a high concentration of

chloride solution that will penetrate the pores of the concrete.

Over tirne, through repeated applications of chloride solution, chlorides eventually reach the

reinforcing steel bars. At a critical concentration of chlorides, providing there is sufficient

oxygen and moisture, corrosion will initiate. The corrosion products are larger than the original

steel, and can be as much as seven times the volume of the original rebar [Thomas, 19971. This

increase in volume causes expansive forces on the concrete, the concrete cracks, and eventuaily

spalls off' From this process, structural deterioration is initiated. The steel becomes exposed and

Chapter 1 - Introduction 2

vulnerable to rapid corrosion, thus decreasing the area of steel available for structural capacity as

well as reducing its bond to concrete.

1.2 Chloride Ingress

The durability of RC can be directly linked to the ease with which fluids can enter concrete. in

most forms of concrete deterioration, such as fieeze and thaw damage, ASR acid attack, sulphate

attack and leaching, fluid is needed. Fluids, typically aqueous solutions, are not only needed for

concrete deterioration, but also for deterioration of the steel reinforcement bars. For example, in

the case of corrosion, durability can be related to the ease of chloride ingress through concrete.

There are six modes or mechanisms that describe how concrete imbibes chloride solution:

sorptivity, diffusion, chloride binding, dispersion, wicking and permeation [Hooton and

McGrath, 19951. The first two, sorptivity and diffusion are the most domhate mechanisms.

1.3 Repair and Maintenance

Many attempts have been made to address the problem of chionde penetration, at different stages

of the concretes service life. At the f is t stage, before any concrete has been cast, structures can

be designed to slow down chloride penetration or provided a barrier. This can be done by using

epoxy coated rebars, increasing the depth of cover, using less permeable concrete or placing a

protective membrane or sealer on the concrete. Membranes or sealers can also be applied after

the concrete has been cast, and has expenenced chloride exposure. The difficulty with

membranes and sealers, is that they must be penodically reapplied, as regular Wear will erode

them away.

The worst case is when the critical chloride concentrations have reached the rebar, and the

chlorides rnust be removed or reduced. The only method of complete chloride removal is to

physically remove the chloride contaminated concrete and replace it with a new concrete. One

method of reducing chloride concentrations at the rebar is through an electrochemical procedure

called electrochemical extraction (ECE). This method applies an anode around the structure

undergoing chlonde induced corrosions, and then with a high voltage, draws out the chlorides.



In some cases, one possible form of remediation could be to use cathodic protection, where the

anodic rebar is forced to become the cathode through the application of a smail voltage. No

method has proven to be completely effective, to prevent chloride ingress, or remove chlorides in

concrete. Therefore to sustain the seMce life, eventually some sort of maintenance or repair will

again be needed.

1.4 The Need for Service Life Modeling

The question now is: 'when should maintenance or repair be made?' Repair and maintenance

are expensive and dificult to implement in the present economic environment as budgets for

Uifrastnicture are ever decreasing. To optimize the limited resources available, cost analyses

need to be performed. To predict this optimum t h e with any degree of accuracy, a model with a

thorough understanding of the six mechanisms of chloride ingress is needed. Such a model must

also take into consideration how the combinations of mechanisms will influence the amount of

chlonde ingress.

1.5 Cyclic Wetting and Drying

Since concrete is generally the extenor component, it must resist severe physical and chemical

attacks. Concrete becomes Milnerable to fiequent exposure to wind, s u , rain, snow, and high

concentrations of chloride solutions. Some combinations of these types of attacks are cyclic in

nature such as freezing and thawing cycles, or wetting and drying cycles.

Extensive research has been done on concrete exposed to fieezing and thawing cycles, and the

physical mechanisms governing this type of attack are well understood. It is known that cyclic

wetting and drying allows for deeper penetration of aggressive ions [Moukwa, 19901, and can

lead to corrosion rates 20 times higher than exposure to a continuous sait fog [Yeomans, 19941.

However, the kinetics of cyclic wening and drying are not Mly understood, and more

investigation is needed.

Cyctic Wetting and Drying and its Effects on Chloride Ingress in Concrete


1.6 Objective and Scope of Research

The objective of this research project is to study the effects of cyclic wetting and drying on

chloride ingress in concrete. A series of cyclic tests were performed to obtain an understanding

of the physical mechanisms causing the accumulation of chlondes in the intenor pores of

concrete during the dryhg and wetting phases of the cycle. Factors such as the effects of the

number of cycles, length of drying phase, and periodic wetting cycles with fresh water will be

discussed.

For the purposes of this study the two main mechanisms were studied: absorption and d i f i ion .

There are six mechanisms (absorption, diffusion, wicking, chioride binding, pexmeation,

dispersion) that c m effect chloride penetrations and these are discussed in more detaii in Section

2.0. Consideration has been made for reducing the effects of wicking, chloride binding,

permeation, and dispersion by either aitering the specimen configurations, or extending testing

tirnes. Absorption and diffusion are studied separately to isolate both their individual and

combined effects.


2.0 Literature Review


C yclic wetting and drying causes continuous moisture movement through concrete pores

[Crumpton, et al., 19891. This cyclic effect accelerates durabiiity problems because it subjects the

concrete to the motion and accumulation of ha& materials, such as sulphates, ahl ies , acids,

and chiorides.

Cyclic wetting and drying is a problem for RC structures exposed to chlorides and its effects are

most severe in mainly three locations:

1. marine structures, particularly in the splash and tidai zones,

2. in parking garages exposed to deicer sdts, and

3. highway structures, such as bridges and other elevated roadways for instance the

Gardner expressway.

When concrete is dry or partially dry, and then exposed to salt water, it will imbibe the salt water

by capillary suction. The concrete will continue to suck in the salt water untii saturation, or until

there is no more reservoir of salt water. A concentration gradient of chlorides will develop in the

concrete, stopping at some point in the interior of the concrete. If the extenial environment

becomes dry, then pure water will evaporate fiom the pores, and salts that were originally in

solution may precipitate out in the pores close to the surface. The point of highest chloride

concentration rnay now exist within the concrete. On subsequent wetting, more sait solution will

enter the pores, while re-dissolving and canying existing chlorides deeper into the concrete.

The rate to which the chlorides will penetrate the concrete depends on the duration of the wetting

and the drying periods. If the concrete remains wet, some salts may migrate in from the concrete

surface by diffusion. However, if the wetting penod is short, the entry of salt water by absorption

will cany the salts into the interior the concrete and be M e r concentrated during drying.

Chapter 2 - Liternhire Review 6

Cyclic wetting and drying increases the concentrations of ions such as chlorides, by evaporation

of water. The drying of the concrete also helps to increase the availability of the oxygen required

for steel corrosion, as oxygen has a substantially lower diffusion coefficient in saturated concrete.

In fact diaision of oxygen through air can be as high as 10,000 times the diffusion of oxygen in

water [Escalante, 19901. As the concrete dries and the pores become less saturated, oxygen will

have a better chance to diffuse into the concrete and attain the level necessary to induce and

sustain corrosion. For example; concrete structures subjected to seawater wetting and drying

exposure are most prone to detenoration, compared to concrete structures pemanently

submerged in seawater [Abdul-Hamid, 19901. in this case there is an increased availability of

oxygen that also contributes to the deterioration compared to the subrnerged part of the structure.

As well, for the concrete that is Mly submerged, less chlonde would enter the concrete as the

dominant penetration rnechanism is diffusion through the pore solution.

There are several factors that can affect the degree that chlorides will enter concrete through

cyclic wetting and drymg. The ingress of chlorides into concrete is strongly influenced by the

sequence of wetîing and drymg, and on the duration. Specifically, the degree of dryness is very

important, and therefore the dryhg conditions. Drying to a greater depth (chier concrete) allows

subsequent wettings to carry the chlondes deeper into the concrete, thus speeding up the

penetration of chloride ions [Neville, 19961. In fact the moistute content, or in other words, the

extent of drying in the concrete "has a direct influence on durability, as it govems the amount of

oxygen and moisture available at the rebat, and the magnitude of the capillary suction forces,

which dictates the rate of penetration of water" WcCarter et al, 19971.

2.1.1 Concrete Drying

Similar to other porous media, concrete dries in two stages [Selih et al., 19961. The

initial portion occurs in the first 3 to 7 days, and in the initial stages of dryuig, the rate of

drying is high and constant. This constant drying rate shows that there is a presence of

fiee liquid water in the concrete. The outward flow of water is driven by capillary forces

[Selih et al., 19961. During the second penod, when saturation rates are much lower, the

drying rate decreases with time. The rate of dryhg is related to the square root of tirne,


Chapter 2 - Literatiire Review 7

since it is also a diffusion process. When the concrete reduces to a moishue content of 70

- 80 % of its the initial saturation, the rate of drying becomes controlIed by diffusion

[Selih et al.. 19961.

In general there are two conditions that can alter the rate of concrete drying: relative

hurnidity (RH), and characteristics of the concrete itself. RH is the amount of moisture in

the air relative to the saturated water vapour content, and varies fkom O to 100 %. The rate

of concrete drymg is also af5ected by the microstructure of the concrete, and the materials

with which it was made. In tems of the material, the pore size, pore size distribution,

pore continuity, tortuosity and micro-cracking within the surface region will affect the

rate with which moisture will be ernitted fiom the sample.

2.1.2 Concrete Wetting

The wetting process also occurs in two distinct stage, although wetting occurs faster than

drying. For most concretes, the initial stage of wetting will occur within several hours

and is best represented by the sorptivity equation (Equation 2.4). As the concrete reaches

a certain point of saturation, there is a deviation fiom the square root of time relationship,

that is best explained by a polynomial equations wl, 1987 and McCarter, 19961.

Eventually, when the concrete becomes completely saturated, chloride ingress will follow

the laws of diffusion. Diffusion wiI1 be discussed in more detail in Section 2.3.

2.2 Fluid Ingress

As stated by Hooton [1995], "almost d l forrns of concrete deterioration are influenced by ingress

or movement of fluids in concrete." The definition of fluids in this case c m be gases, such as

carbon dioxide and oxygen, or chemicals like sulphates, chlorides, alkalies, or acids that are

dissolved in water.

There are basically six mechanisms which govem chloride ingress into concrete and they are

[Hooton and McGrath, 19951:

Cyclic Wetting and Drying and its Effects on Chloride Iogress in Concrete

Chapter 2 - Literature Review 8

1. Surface Absorption (Sorptivity): When the concrete surface is not saturated at the

tirne it is exposed to a chloride solution, the capillary tension will draw (or absorb) the

chloride solution into the concrete. For different qualities of concrete, absorption

values are generally related to permeability pooton et al., 19931, and the moisture

content of the concrete [Neville, 19961. Sorptivity is the term used to describe the

rate of absorption.

2. Diffusion: When concrete is saturated and at least one surface is exposed to chloride

solution, then diffusion will occur as the solutions seek to attain equilibriurn causing

the chloride ions fiom high concentrations to rnove to low concentrations.

3. Chloride Binding: Some soluble chloride ions can be consumed or bound in the

hydrated phases of the cernent paste. When chloride binding is not considered, the

predictions for the rate of chloride ingress will be too high. Chloride binding will be

discussed in Section 2.3.

4. Dispersion: As a chlonde fkont diffuses into the concrete cover, the front will tend to

disperse as it travels, and the ions will move faster or slower than the average

diffusion rate. (However, dispersion is not really a mechanism of ingress but an issue

that affects ingress of chlorides).

5. Wicking: Wicking c m occur when a concrete surface away fiom the chloride source

is exposed to air with a relative humidity less than 100%. The pore water will be

drawn towards the surface that has a lower relative humidity, wiil evaporate and pre-

crystalize chlondes. The evaporation, empties the pores and results in W e r

sorption, which in temi causes an increased chloride concentration inside the

concrete.

6. Permeation: This describes the flux of water (or chloride solution ) due to a hydraulic

pressure gradient across the concrete.

For structures exposed to cyclic wetting and drying, absorption and dinusion are the most

significant mechanisms. in fact for building materials such as concrete, when water contents are

less than complete saturation, the capiliary action of the materiai is normally the dominant cause



of flow waii and Yau, 1987. These two mechanism wiil be discussed in more detail in the

following two sections. Chlonde binding will be discussed briefly in Section 2.3.

2.3 Diffusion

As stated in Section 2.1, diaision occurs in saturated concrete that is seeking to anain

equilibrium of chloride ion concentrations throughout it's pore solution. Presently most

theoretical understandings of chloride movements in concrete are based on Ficks laws of

diffusion [McGrath, 19961, and are explained below.

Ficks fvst law states that chloride flux is proportional to concentration gradient.

Equation 2.1

where:

J = Flux (rno~m'.s)

D = Diffusion Coefficient (m2/s)

c = Concentration (moI/m3)

.Y = Depth fiom the surface of the concrete (m)

The followhg three assumptions are made in Ficks first law:

1. the system is at steady state

2. the concentration is the only driving force

3. there is no interaction between d i k i n g ions and the solution.

Ficks second law of diaision which is developed by considering mass conservation in a unit

control volume is used to calculate the rate of change of the species concentration with the

following relationship :

where :

t = Time (s)

Equation 2.2

- - -- -


Chapter 2 - Litenihire Review I O

When Ficks nrst and second laws are combined, the solution to the differential equation can be

obtained using Cranks solution, while assuming the following three boundary conditions:

1. c = c,, at x = 0, and t > O, where c, is the concentration of chlorides at x = O, t > O

(moI/m3)

2. c = O, when x > 0, and t = 0, the initial condition, and

3. c = O, when x = ao , and t >> 0, the infinite condition,

Crankç solution is [Crank, 19751:

Equation 2.3

where:

c(,q = Concentration of chlorides at distance x and tirne t (mol/m3)

erf = Error function (a numericd fûnction available in mathematical tables)

Commonly diffusion coefficients are denved fiom concentration profiles using Ficks laws of

diffusion and Cranks solution pentz et al, 19961. These profiles and coefficients are helpful for

estimating the time to corrosion of RC structures [West and Hime, 19851.

There are many variables that c m affect the diffusion coefficient. The fvst assumption of a

steady state, is never tnily the case. Concrete is a hydraulic matenal which will continually

hydrate, given that there is available moisture. With continued hydration, the pore structure will

continue to rehe , and subsequently lower the diffûsion coefficient with tirne.

Another factor that affects the di&ion coefficient is chlonde binding. Chlorides exist in three

States perman, 19721:

1. fieely in the pore solution

2. chemically bound to hydration products, and

3. physically held to the surface of hydration products.

- - - - - - - - --

Cycüc Wetting and Drying and its Effects on Chloride Ingres~ in Concrete

Chapter 2 - Liternture Review I I

Although presently it is not understood how the three states of chlorides are partitioned

WcGrath, 19961, it is believed that reducing the chlorides in one state will effect the

concentration of the other two states. It is thought that most bound chlorides are physically

bound to ion exchange sites on the calcium siiicate hydrate (CSH) gel, implying a significant

degree of reversibility [Tang and Nilsson, 19931. Therefore reducing the chloride concentration

in the pore solution will cause bound chlorides to becorne fiee. However, chloride binding is

normaily not considered since the reaction rate of binding is thought to be completed faster

(seven days) than the d i f i i o n rate [Tang and Nilsson, 19931.

A third significant factor that affects diffusion coefficients is the fact that most structures do not

expenence a consistently saturated moisture condition. Tme diffusion occm when concrete is

saturated. Yet RC structures are subjected to a variety of moisture states, where water and

vapour flow in and out of concrete by capillary suction through continuous pores.

Even with the many variables that exist, d i f i i o n has proven to be a reasonable estimator for old

chioride contarninated structures that experience a fairly consistent environment [West and

Hime, 19851. Over an extended period of tirne, the variables that tend to decrease the effective

diffusion coefficient, such as chlonde binding, and continued hydration, cancel out the variables

that tend to increase the diffusion coefficient, such as vaqhg moisture states. However, the

problems of significant early deterioration in RC structures are occwbg in structures that

expenence frequent environmental changes, such as cyclic wetting and drying. Therefore,

considering diffusion alone in service life modeling is not sunicient for most structures, and

more research is needed to incorporate other mechanisms, especially sorptivity.

2.4 Sorptivity (Rate of Absorption)

Sorptivity, the rate of water absorption, is a rapid and simple test that can provide an indication

of the transport properties of cover concrete parrott, 19941, and its tendency to absorb and

transmit water by capillarity Wall, 19891. Sorptivity can be dehed in two ways: the

accumulative volume of water for a given area of concrete, or the rate of water penetration with



respect to depth WcCarter 19921. In most cases sorptivity testing usually refers to the f i t

deriition.

Sorptivity in general has the following relationship [Hall and Ya y 1 9871:

I = A+s~"' Equation 2.3

where :

I = Accumulative volume absorbed/unit area inflow surface (mm3/mrn' = mm)

A = Intercept at t = O due to rapid fiiiing of open surface pores (mm)

S = Sorptivity of materiai ( r n m / j s )

t = Elapsed t h e (min)

There are four requirements that must be met for the water absorption vs 4 s Iaw to hold, and

they are [Hall and Tse, 1 9861:

1. the matenal must be hornogeneous on the scale of the penetration distance

2. the capiilary absorption flow must be normal to the inflow face (not converging or

diverging)

3. water must be fieely available at the innow surface (by direct contact with an

unlimited) reservoir and

4. gravitational effects must not be apparent on the absorption.

With al1 these requirements met, the Jtime law accurately describes the kinetics of capiilary

absorption (sorptivity). A cornmon method of testing sorptivity is illustrated below.

I l t t t t l I

Figure 2.1 Sorptivity Test



The sorptivity relationship S, c m be represented by a straight line, and can be detexmined by the

slope of the least-squares linear regression line, given 8 > 0.98. The ongin is not inciuded in the

linear regession curve for obtaining the sorptivity or slope of the absorption vs curve.

Often the relationship displays non-linear behaviour during the fbst few minutes, as the paste

skin becomes saturated. Afier this fkst stage, the area of absorption is smaller, due to the

presence of aggregate, giving a srnaller sorptivity value PeSouza, 19961.

Over an extended perîod of time of several hours (depending on the concrete, this can be 24 to 48

hours), the sorptivity will no longer be linear, giving the sorptivity relationship two distinct

regions. In long term sorptivity tests it was found that there was a significant deviation fiom

linearity w l and Yau, 19871. In these cases the data was better described by the following

polynomial equation :

I = A+s~"' -Ct Equation 2.4

where :

C = A constant [mrn/min]

It is believed that this discontinuity is due to the existence of a saturation gradient between the

exposed surface and the interior part of the concrete WcCarter, 19961. It would seem that as the

wetting front reaches saturation in the concrete, gradually the wetting charactenstics are better

described by diffusion, rather than sorptivity.

It is important that the test specimens are conditioned to a defined initial state of dryness, before

taking any measurements, for sorptivity is closely linked to the moisture content of the concrete.

Considering sorptivity's high sensitivity to moisture contents, there are several factors that can

affect its value. Care must be taken to ensure that the water content of the concrete is uniform

[Hall, 19891. Parrott in 1994 presented a drying method, where partial drymg at 50°C followed

by seded storage at 50°C for a few days provided a fast and convenient method of obtaining a

uniform moisture distribution. This method of drymg also ensures a relative humidity in the

concrete that is within the range that most stmchual concretes exist in service. DeSouza [1996]



performed M e r tests with various drying times, and found that a drying regime of 3 days at

50°C followed by 4 &ys in a seaied container at 50°C would produce a moishire content of about

1% and a surface relative humidity of approximately 40%. The additional tirne in the sealed

containers allowed moistue to re-distribute within the concrete thus creating a uniform rnoisture

content.

Other factors that can affect the sorptivity values of concrete are the sorptivity properties of the

individual components of the concrete such as the cernent paste ma& and its physical

arrangement, for example the aggregate distribution [McCarter et al. 19921. In generai the most

porous part of concrete is the cernent matrix, more specificaily, the interstital transition zones

(ITZ). The ITZ is the interface between the cernent paste and the aggregate, which is typically

the most porous part of concrete, and it is this part that has the greatest effect on sorptivity. The

aggregate distribution will govem the amount of ITZ, and therefore will affect the sorptivity

values.

Sorptivity measurements can be made with any wetting fluid, although it is conventionally

measured with pure water. When other wetting fluids are used it is found that sorptivity varies

in proportion to the quantity ( ~ l ~ ) ' ~ , where o is the surface tension and q is the viscosity [Hall,

19891. In the case of salt soiutions, it was found that the sorptivity values for 2, 4 and 10%

chioride solutions were similar to that of water waclnnis and Nathawad, 198O].

Cyctic Wetting and Drying and its Effects on Chloride Ingres in Concrete

3.0 Experimental Program

3.1 Overview

As stated previously, the objective of this work is to examine the effect of cyclic wetting and

drying and its effects on two primary mechanisms of chloride ingress: absorption and diffusion.

The primary goal was to obtain information regarding the effect of the length of cycles and the

number of cycles on the degree of chloride ingress in concrete. Two cycle lengths were chosen,

where the wetting time of six hours was kept constant and the tirne of drylng was either 18 h o m

(One-day cycle), or 66 hours (Three-day cycle).

Diffusion tests for 120 days and one year were perforrned and sorptivity testing was conducted

according to the Draft ASTM Sorptivity test. As well tests were completed according to the

ASTM C 642 test for percentage of absorption, bulk specific gravity and percentage of voids.

Three concrete mixes were chosen to be tested.

3.2 Ma terials

The following three mix designs were chosen:

1. 0.4w/c, with25%slag

2. 0.4 w/c, with 25% slag and 8% silica fume

3. 0.3 w/c, with 25% slag and 8% silica fume.

These mixes were selected because they al1 meet the requirement of CSA A23.1 Exposure Class

C-l for structures such as bridge decks exposed to de-icing salts in the Toronto area. The

Ministry of Transportation (MTO), through its OPSS (Ontario Provincial Standard

Specifications) for concrete has specified an upper limit of 25% slag for it's concrete. As MT0

is one of the largest users of concrete, mix designs with these considerations were used, and can

be found in Table 3.1. Al1 specimens fiom Mixture 1 were given the prefk identification KHI,

and similarly Mixtures 2 and 3 were given the prefk identifications KH.2 and KH3.

Chapter 3 - Experimental Program 16

Table 3.1 Mu Desips

Portland Cernent - Woodstock Type 10 Slag - Standard Silica Fume - SKW Beancour Corne Aggregate - Dufferin 10 mm Fine Aggregate - Nelson Water Water Reducer - 25 XL (mi/ 100 kg) Superplasticizer - SPN (mV100 kg) Air Entrainer - Micro Air ( d l 00 kg)

The raw materials used for the three mixes are shown in Table 3.2. Chemical analysis for

cementitious materials can be found in Appendix A.

Table 3.2 Raw Materials

Mater ial Cernent S lag Silica Fume Coarse Aggregate Fine Aggregate Water Water Reducer Superplasticizer

Air Entrainer

Type Cornments Large Bath Plant CSA A5 Type 10 or 20 Largarge/S tandard S lag Fruitland Plant CSA A23.5 SKW in Becancour Quebec CSA A23 -5 Type U Standard DufTerin 1Om.m CSA A23.1 Absorption: 1.67% Nelson Crushed Limestone CSA A23.l Absorption: 1.4% Tap Water 25 XL Lignosulphonate based SPN Sodium naphthaiene fomaldehyde

condensate Micro Air Pure polymeric base

3.2.1 Method of Mixing

Several days pnor to mixing, ail the coarse aggregate was washed to remove any €me dust

that may increase the water demand, and lower the bond strength. The wet coarse

aggregate was then sealed in a bucket, and at least one &y was allowed for absorption,

the moisture content of the aggregate to stabilize and the excess water to drain to the

bottom of the bucket. The coarse aggregate in the bottom portion (5-1 0 cm) of the bucket

was not used, as it would be wet fkom the excess water. Prior to mixing, the materials

were batched into sealed buckets at least one day in advance. Moisture contents were


Chapter 3 - Experimentel Program 17

taken of the fine and coarse aggregate, the &y before each cast, and the batched masses

for the aggregates and water were adjusted to obtain an overall saturated surface dry

condition for the aggregate.

A 1 40 L Eirich R2 flat plan mixer was used for the mixes. Before the actual mix, a butter

rnix was made with the same mix design as the actually mix. This was to coat the intenor

of the mixer and the paddles with cernent paste, to compensate for the cernent paste that

would be lost fiom coating the mixer. The butter rnix was then discarded.

The batched aggregate, cernent and SCM was divided into two equal portions, as the

capacity of the hopper was not sufficient for the size of the mix, and needed to be filled

twice. The coarse aggregate was first placed in the hopper, as its particle size was large

enough to not slip through the edges of the hopper. The cernent and SCM would be

placed on top of the coarse aggregate, and next the sand to prevent dust fiom the fine

cernentitious materials. Air entrainer was evenly poured on the second half of the sand,

before the contents of the hopper were dumped into the mixer. The dry materiais were

mixed fïrst, until a homogenous mixture was achieved (approxirnately 30 - 60 seconds).

Then the water with the water reducer was added to the mix, and the timer was started as

soon as the water was added. The mixing sequence used is Iisted in Table 3.3. The

mixing sequence was divided into two sections to allow for adjustrnents in the total

amount of superplasticizer, f i e r testing for slurnp.

Table 3.3 MUring Sequence

Rest Mix Rest Mix

ActiviS, Mix

Mix Rest Mix

Time EZapsed T h e Cornrnents 3 0-3 M e r 1 % min. add % of Superplasticizer ' 2 3-5

2 5-7 2 7-9 1 9- 1 O Test air content and slurnp fiom the mixer

10-20 2 20-22 Add the rest of the Superplasticizer as needed 2 22-24 1 24-25 Dump concrete and test for air content, slump

and plastic density


Chapter 3 - Experirnental Program 18

3.2.2 Curhg

All concrete was cured using the same method. Once the concrete had been placed and

finished, it was cured under wet burlap and plastic in the concrete lab environment for the

first 24 k 2 hours. The forms were then removed, and the concrete was submerged in a

saturated lime water tank at room temperature for 27 more days. To obtain saturated lime

water, 1.5 g of Ca(OH)2 is needed for every litre of regular tap water. To ensure that the

lime water was t d y sahuateci, 3.0 g of C a ( O Q was used for every litre of water.


There were two series of cyclic wenuig and drying perfonned, a One-day cycle and a Three-day

cycle. During a One-day cycle, the samples were placed in a sealed chamber f i e r being surface

dried with compressed air. in the chamber were three 250 ml beakers of saturated Ca& solution

to help Lower the relative humidity in the chamber. The equilibrium relative humidity of CaCll

solution is 29% at 25OC [Young, 19671. Monitoring of a similar chamber showed that the

relative hurnidity values cycled between 50 - 80%. As moist samples were placed in the

container, the relative hurnidity would nse to a hi& of 80% then graduaily fa11 to a low of 50%.

Afier 18 hours of drymg in this chamber, the samples were removed, and placed into containers

of 1 .O molar NaCl solutions, where they were lefi for six hours. This combination of six hours of

wetting and 18 hours of drying was chosen for the One-&y senes, because it is known that the

rate of wening is faster than then rate of drymg. It has been s h o w that in certain circumstances

that the rate of wetting can occur 3-7 tirnes faster than the rate of drying WcCarter, 19971.

The NaCl solution was made with one mole (58.44 g) of NaCl, that has been dried at 1 10°C for

at least 24 hours, and 1 .O L of distilled water (Note: for high concentrations of salt solution, such

as 5.0 molar NaCl solution, 5.0 moles of NaCl should be used to make 1.0 L of solution and not

1 .O L of solvent). The same type of 2.5 L square plastic containers were used for al1 cyclic tests,

and each container was filled with 1.5 L of solution and a pair of specimens.



At the end of the sixth hour, the samples were removed fiom the containers, and surfaced dned

with compressed air. This would complete one cycle. Lf M e r cycles were to be administered

they were then retumed to the enclosed chamber to begin the dryhg stage, followed by wetting

with salt solution.

Six pairs of samples were designated for the One-day series. One pair of specimen was subjected

to 1 cycle, another pair to 4, and similady 9, 16, 25, or 36 cycles. This portion of the

experimental program was designed to examine the effect of increasing the number of cycles, on

the depth of chlonde hgress.

However, in the spring, as there is rain, the concrete is exposed to fresh water that is very low in

chloride concentration and some of the chlorides in the concrete would be washed out. To

examine this effect, three pairs of specimens were subjected to 25 cycles of salt solution followed

by 4, 9 or 25 cycles with distilled water for Mixes i and 2. For Mix 3, the three extra pairs of

specirnens expenenced 4, 16, or 25 cycles with distilled water after the 25 cycles with salt

solution. At the completion of the prescnbed number of cycles, the specimens were tightly

quadruple wrapped in fieezer bags, and stored in a fieezer (-18OC) to prevent M e r chloride

diffusion. At a later date these samples were analyzed for chiorides, and chloride profiles of the

samples were established. Details of this analysis are given in Section 3.5.

Another five pairs of specimens were designated for the Three-day series, and exposed to 1,1, 9,

16 or 25 cycles of wetting and drying with sait solution. For this series, the specimens were

allowed to dry in the enclosed chamber for 66 hours instead of 1 8 hours.

33.1 Sample Identification

The specimens were systematicdly labeled to easily keep inventory of them, as there

were 14 types of cycles, nine in the One-day series, and five in the Three-day series. Each

specimen indicated the mix, the senes, the type of test it was undergoing, the number of

cycles and which replicate it represented. For example KHI-lP4- 1, identifies that the

specimen was from Mix &One-day series, undergoing cyclic testing (to be later anaiyzed

Cyclic Wettlng and Drying and its Effects on Chloride Ingress in Concrete


to obtain its chloride profile, givhg it a P designation), exposed to four cycles, and it is

the fïrst replicate. A description of al1 samples and theu identification numbers are given

in Appendix B. Figure 3.1, outlines the timeline needed to complete this cyclic testing,

and details of the testing schedule can be seen in Appendix B.

- - - - - - - - - - --

Figure 3.1 Timeline for Cyclic Testing

3.3.2 Specimen Preparation

From each slab, specimens were cored on the 23rd and 24h day with a LONGYEAR b*24"

Drill, and sliced with a TARGET diamond-bladed rock cutting saw. Six 100 k 3 mm

diameter specimens were cored fiom five slabs to provide the 28 (14 pairs) cores needed

for the cyclic wetting and drying testing program. The specimens were saw cut to a

thickness of 50 + 3 mm, giving each specimen a saw cut finish on the bottom and a form

face finish on the top, which wodd be the test face. The form face rather than the

f ~ s h e d face was used as the testing surface, as the form face would give a more

consistent finish compared to the trowel finish.



Once the specimens had been cored and saw cut, they were dried off with paper towels in

preparation for sealing, with a Cappar Caprock EX Grey epoxy. The test face was taped

with masking tape, and the remaining sides were coated with a continuous layer of epoxy.

This was done to eliminate the effects of wicking and to ensure unidirectional chloride

penetration of the test face. M e r six hours had passed to allow the epoxy to harden, each

specimen was examined to ensure no air pockets had fonned in the epoxy. Coatings were

patched as necessary. Patched samples were allowed an additional six hours for the patch

to harden and then retumed to the sahuated lime water tank for curing until testing on the

28" day.

3.4 Diffusion

Diffusion tested specimens were cored and epoxied in the same fashion as the cyclic tested

specimens, as described in Section 3.3.2.

After surface drying with compressed air to remove surface moisture, debris and Ca(OH)2 fiom

the curing tank, a pair of samples fiom each mix was placed directly into a 2.5 L square plastic

container, with 1.5 L of 1.0 molar salt solution. Afier 120 days, one sarnple was removed,

surfaced dried, and quadruple wrapped in freezer bags to be stored for future chloride profile

analysis, wtich will be discussed in detail in the following section. A dummy specimen that was

sealed on al1 sides with epoxy, was placed back into the same container to maintain the same

ratio of ponding solution volume to specimen volume. The second specimen was removed after

one year fiom fist exposure to 1 .O molar NaCl solution at 23OC.

Another five pairs of samples were reserved for diffusion tests. One pair of samples was dried in

the same enclosed chamber used for the cyclic testing (at 23OC, with a relative humidity of 50 - 80%) for one day, before placing in the salt solution for 1 19 days. A second pair of samples was

placed in the drying charnber for three days and then placed in a salt solution for 1 17 days. This

was to evaluate the ef5ect of partially sahirated concrete on diffusion.

Cycüc Wetting and Drying and its Effects on Chloride Ingress in Concrete

Chapter 3 - Experimental Program

The last three pairs of specimens were placed immediately into salt solutions for 120 days, and

then one pair was placed in distilled water for 30 days, the second for 60 days, and the last pair

for 120 days. The purpose of these sarnples was to examine the degree of back diffusion of

chlorides in fiesh water. Figure 3.2, outlines the timeline needed to cornpiete the dithision tests.

Details of the testing schedule can be seen in Appendix B.

1 Day Cond. 11 9 Days Diffusion 3 Oay Cod . 11 7 Days Diffus~on

ays Water

It. 00 Oays

120 Days

Waîer

Sait. 120 Days Water

I Dhtilled Wabr Cycles l Figure 3.2 Timeline for Diffusion Testing

At the conclusion of the diffusion tests al1 samples were surface dned 6 t h compressed air, and

then quadruple sealed in freezer bags, to be stored fiozen (-18°C) for Iater chloride profile

analysis, which will be discussed in detail in the following section.

3.5 Chloride Analysis

To perform a chloride analysis, thin layers of concrete sample need to be obtained. These layers

are then digested or decomposed with nitric acid to release the chlorides in the concrete. The

concentration of the chiondes at the given depth are determined through titration with Silver

Nitrate (AgN03). The chloide concentrations were then be used to compose a chloride profile

of the sample. The following sections will explain how the samples were analyzed for chloride

content. Al1 equipment used for chloride analysis was cleaned in an ultrasound bath and rinsed

thoroughly with distilled water before they were used.

3.5.1 Grinding

Specimens were removed fiom the fieezer just prior to being ground. The epoxy - coated

surface that would fdl within the grinding path was chipped off with a hammer and wide


Chapter 3 - Experirnental Program 23

heavy chisel. The sample was chipped in this manner to prevent the contamination of the

ground sample with epoxy, as illustrated in Figure 3 -3.

Grinding Path

Figure 3.3 Prepared Sample for Grinding

The specimen was clamped into a Van Norman milling machine with a vice and either a

rnetal V block, or a formed wooden block, such that the grinding bit was parallel to the

top of the test face. The first layer was discarded, as surface imperfections tend to cause

accumulation of the chloride solution, resuiting in higher values of chloride

concentrations. Ground layers were between 0.5 1 to 0.76 mm (0.020 to 0.030 inches)

thick.

An estimation of the depth of chloride penetration was made based on previously

obtained profiles of similar concrete with similar exposures. To obtain a good chloride

profile, a minimum of five data points in the penetration zone and one point just beyond

the penetration zone was required. As a result, generally 10 samples were taken to

characterize the chloride profile, with more points taken at the surface of the specimen.

These samples were then dried to a constant mass in the oven at 1 10°C. The four edges

of the core sample were measured aller grinding, and adjustments in the recorded depths

were made assuming any erron occurred during the original setting of the specimen in the

milling machine.



3.5.2 Nitric Acid Digestion

Samples were cooled in a desiccator on the &y of analysis. Each sample was then

separately sieved through a 3 15 micron sieve. Larger chips that were retained were

discarded, as they would likely contain materiai from other layers. From the sieved

sample, 2.0 g of powdered sample was weighed out fiom each layer into a dry 250

ml glass beaker, and set aside to be digested with nitric acid.

The digestion process was then complete in the following manner:

a 1 : 1 nitric acid solution (nitric acid : distilled water) was prepared,

35 f 5 ml of distiiled water, and 7 k 0.1 ml of nitric acid solution was measured

out.

a stop watch was staried as the distilled water was added to the 2.0 g sample

followed immediately with the nitric acid solution, and approximately 1 ml of 30

percent hydrogen peroxide, (this was to prevent sulphide complexes fiom

intedering with the titration process, as siag which has a high concentration of

sulphide sulphur was used in every mix [AASHTO T260-941).

the mixture was stirred with a glass stir rod for 20 seconds, and the rod was then

rinsed into the beaker with distilled water.

the beaker was then covered with a watch glass and set aside unti14 minutes have

passed since the stop watch was started.

the mixture was then placed on a pre-heated hot plate, brought to a boil and

promptly removed (Note: Berman [1972] suggested that chlorides cm be Iost

through vaporisation, if the mixture is ailowed to boil for any length of tirne).

Once the digested sample had cooled enough to handle safely, each sample was fiItered to

remove any solid particles. The following filtering procedure was used:

1. using mbber tubing, a water trap was connected to a vacuum purnp, and then a

250 ml glass nIter flasks with a plastic 90 mm buchner filter funnels was attached,

and medium grade (couse porosity, fast flowing) filter paper was placed in the

funnel.

Cyclic Wetting and Drying and its Effects on Chlonde Ingress in Concrete


two doses (of approximately 25 ml) of distilled water were passed through the

filter paper and the edges of the funne1 were then rinsed with distilled water while

the pump was running, and the water was discarded (this was done to rime out the

entire filter system and filter paper)

the digested sample was then slowly poured onto the centre portion of the funnel

(care was taken to not allow any material to be pulled over and under the edge of

the filter paper), and the beaker was rinsed with distilled water to filter out any

residue on the beaker

after the solution had been pulled through the filter, the funnel was rinsed twice

with distilled water

the solution was then poured back into the original beaker and the flask was rinsed

twice into the beaker, and covereci with the watch glass.

Titration

Prier to titration, the filtered sample was allowed to cool to room temperature. The

sample was them analyzed for total chlonde content by using a potentiometric titration,

with 0.01 molL AgNOj solution and a silver billet electrode. The chloride concentration

was computed £rom the inflection point of a plot of the potential versus titrant volume.

The titrant was dispensed by an automatic Metrohrn DMS 760 automatic titrator.

A sub-sample (volume between 5 - 60 ml), of the filtered sample was taken into a 100 ml

beaker. The size of the sample wouid be taken based on an estimated chloride

concentration of the sample. For samples with an expected high concentration of

chlorides, a small sub-sample wouid be taken and vice versa for low concentrations of

chiondes, a larger sub-sample wodd be taken. This was done to reduce the amount of

time and titrant needed to detennine the chIoride concentrations, while care was taken

that sf ic ient amounts of tritrant were used to reduce statistical error (approximately 2

ml).

Cyclic Wetüng and Drying and its Effects on Chloride Ingress in Concrete

Chapter 3 - Experimentsl Program 26

3.6 Sorptivity Testing

Sorptivity tests were performed on three samples after one day of drying in the enclosed

chamber, and another three samples after dryinging for three days. This was done to see if

increasing the drying period would have a significant eEect on the sorptivity. Six 100 t 3 mm

diameter specimens were cored fiom a 350 x 250 x 75 mm slab, and saw cut for a thickness of 50

k 3 mm, in the same marner as for the cyclic testing in Section 3.3.2.

The sorptivity testing procedure that was followed, was based on the ASTM drafl procedure

[1993] developed by Hooton and is as follows:

d e r the prescribed conditioning, the samples were weighed

the sides of the specimen were seaied with vinyl elecûicians tape, and weighed again

(the sides were sealed to prevent absorption of water into the sides, and evaporation

of intemal water, while modeling a segment of an infinite slab)

a pan was filled with water, 1-3 mm above the top of a supporting plexiglass grid,

the sample was weighed just pnor to testing, and this was taken as the initial mass,

the stop watch was started, and the specimen was placed on the supporting grid for 1

minute

the specimen was quickiy removed fÎom the pan, and the stop watch was

sirnultaneously stopped as the surface water was removed by sliding the moist surface

of the specimen over a pile of rnoistened paper towels, and droplets fiom the sides of

the sample were wiped away with another papa towel, and quickly weighed

the sample was placed directly back on the grid of water, and the stop watch re-started

steps 5-7 were repeated for the following total elapsed times of 2, 3, 4, 6 , 9, 12, 16,

20, and 25 minutes fiom the start of the test

the accumulated volume of water absorbed per unit area was plotted vs. the square

root of time in minutes, and the least squares linear regression analysis was used to

determine the sorptivity value, which is the slope of the graph.

- - - - ----- -



3.7 Absorption

The procedure followed for the Absorption test was the ASTM C 642 (Standard Test Method for

Specific Gravity, Absorption, and Voids in Hardened Concrete). For the purposes of this study.

this test was conducted to evaluate the structure of the concrete by determining the percent

absorption and percent of void space. This test was performed on specimens made fiom a small

remixes of the three mix designs. Three specimens were saw cut frorn a cylinder on the 27" day

for the Mix 1, and on the 25" &y for Mix 2 and Mix 3. The following procedure was followed:

specimens were removed fiom the curing tank, and surface dried with compressed air

samples were weighed, and then placed in an oven at 105 - 1 l O°C

24 hours later the samples were placed in a dessicator to cool for 1 hou, re-weighed

and then retumed to the oven,

24 hours later the samples were again cooled for 1 hour, then weighed,

the weights were compared, and if the difTerence between the weights of the two

successive weighings exceeded 0.5% of the lesser weight, they were retumed to the

oven for another 24 hours of drymg, until a constant weight was obtained, and this

weight was designated the dry mass ("A").

once the specimens had cooled completely, they were placed in water, and the

saturated surface dry weights were taken every 24 hours, until constant mass had been

obtained, such that the ciifference in successive weights was less than 0.5% of the

heavier weight, and this was designated the saturated weight d e r immersion ("B")

the specimens were then placed in a pot, and covered with tap water and brought to a

boil, and boiled for 5 hours (care was taken that the specimens remauied covered with

boiling water for the duration of the 5 hours)

afier boiling, cooling by naturai heat loss was allowed, for a minimum of 14 hours, to

room temperature, where samples were surface dried, weighed, and this weight was

designated the saturated weight a£ter immersion and boiling ("C")

the samples were then placed in a non-absorbent mesh basket, suspended by a wire

and weighed in water, and this weight was designated the immersed weight ("Dm)



With the weights determined from above, the following equations were used to determine the

percentage of absorption, bulk specific gravity and percentage of voids:

Percent absorption after immersion and boiling,

Bulk Specific Gravity, Dry

Percent volume of permeable pore space (voids),

3.8 Compressive Strength Testing

A BSGD=-

C - D

The compressive strength was rneasured on the 7h and 28" day. Three 100 x 200 mm cylinden

were tested for compression by loading satwated specimens at a loading rate of 1.9 kN/s. The

ends of the cylindea were ground to ensure the top and bottom were parailel, to pmvent eccentric

loading during testing. Two diameter measurements were made fiom the top and two fiom the

bottom to determine the average area of the cylinders. Length rneasurements were also made to

ensure a 1:2 diarneter:length ratio. The ultimate failure Ioad and average area were used to

detemine the compressive strength of the concrete, and can be found in Appendix A.

Cyelic Wetting and Drying and its Effects on Chlonde Ingress in Concrete

4.0 Results and Discussion

4.1 Overview

The results h m the experimentd testhg will be presented in the following sections. Only a

sumrnary of the data, and pertinent information will be presented for an overview of al1 the

results and for the purposes of discussion. Al1 the results are presented in detail in the

appropriate appendices.

The results of the experimental program are separated into five sections. The fint section offers

the results of tests on the fiesh plastic concrete, the compressive strength and absorptive

properties of hardened concrete. The remaining four sections provide the results fiom the cyclic

testing with salt solution, cyclic testing with distilled water, d i h i o n tests, and sorptivity tests.

4.2 Material Properties

Three mix designs were selected that meet the requirements of CSA A23.1 Exposure Class C-1

structures. To ensure that the cast concrete did actually meet these requirements (maximum w/c

= 0.40, min f c = 35 MPa, air content of 5 - 8%), the plastic properties and the compressive

strength of the concrete were tested. The results nom these tests are shown in Table 4.1.

Table 4.1 Material Properties

1 Shmp Air Plastic 7Day 28Day

The target range for the slump and air was 100 - 150 mm and 5 - 8% respectively. The air

content for Mix 1 was above the desirable range, aithough it was decided to use this concrete as

the entrained air content is a minor factor in the transport mechanisms in concrete. Entrained air

consists of sphericai bubbles that are small (with a typical diameter of 50 p), and discrete, and

Mix 1 (W/C 0.4, 25% slag) Mix 2 (w/c 0.4, 25% slag, 8% SF) Mix 3 (w/c 0.3,25% slag, 8% SF)

[mm] Content Demiiy Strength Strength PA] [kg/m3] [ W a ] [MPaJ

150 9.0 2274 27.3 39.6 95 7.0 2302 34.8 49.2 135 4.5 2260 62.5 79.0

Chapter 4 - Results and Discussion 30

thus do not increase the penneability of concrete [Neville, 19961. Although air entraining does

not Uicrease the permeability of the concrete, the thRe concrete mixes chosen were entrained, in

an atternpt to meet the requirements of CSA A23.1 Exposure Class C-1 stmctures, not exposed

to fieeze thaw cycles.

The ASTM C 642 test for percentage absorption, bulk specific gravi@ and percentage voids in

hardened concrete was performed on a set of samples made fiom small re-mixes of Mixes 1, 2

and 3. The same materials were used in these re-mixes, except for the slag which was from a

different shipment, but was of the same type. The results are s h o w in Table 4.2 and give an

indication of the overall structure of the concretes. These results clearly rank the concretes

showing that they are progressively of a higher quality in tems of the ability of the concrete to

absorb fluids, its bullc specific gravity and percentage volume of permeable pore space.

Table 4.2 Absorption, Bulk Specific Gravity, and Volume of Permeable Pores L

% Absorption % Volume of After Bulk Specific Permea ble

I

Mix 1 (W/C 0.4, Imm & Boil Gravity Dry Pore Space

1

5.82 2.30 13.38 25% slag)

r

Mix 2 (w/c 0.4,

1 25% slaa. 8% SFI 1 f

5.08 2.32 1 1 -78 25% dag. 8% SF)

Mix 3 (W/C 0.3,

4.3 Cycüc Wetting and Drying

Each specirnen that undenvent cyclic testing was chlonde profiled. Chloride contents in units of

parts per million @pm) were measured using the method outlined in Section 3.5. The lowest

value obtained was taken to be the background chloride content of the concrete. The background

chloride content consists of the chiondes that exist in the original concrete as a result of chlorides

in the aggregates, cementitous matenais, admixtures or in the water used to make the concrete.

The chloride values obtained fiom the andysis were the total (acid soluble) chloride content.

These values were then reduced by the background chlorides, and with this idonnation, a

chloride profile was made for each sample in ternis of chloride content by % of concrete mass.

4.27 2.34 9.99


Chapter 4 - Results and Discussion 3 1

This simple conversion, involves dividing the chlorides in ppm by 10 000 (divided by 1 000 000

and multiplied by 100%).

The chlonde profles were then analyzed by visual inspection to determine the depth of

penetration, and to note the overall shape of the profile to obtain some evidence as to the type of

processes that had occurred.

As well, the apparent sorption coefficient, and surface concentrations were determine using

Cranks solution to Ficks second law, given in Section 2.3. The use of Ficks second law to

calculate a sorption coefficient is not really valid, since the chiorides are entering by sorption

rather than a chloride concentration gradient, however both mechanisms are related to the

j z . These numerical descriptions of the chloide profile created a relative basis for

cornparing the sorption characteristics of the specimens, as they were exposed to a various

number and duration of chloride exposure cycles. Chioride profiles, with predicted chloride

profiles resulting fkom these coefficients can be found in Appendix C.

The commercial software package, TableCurve Windows v1.10 by landel Scientific was used to

obtain the apparent sorption coefficients and surface chlonde concentrations. When anaiyzing

the profiles, the E s t point was often ignored, as the chionde solution can accumulate at surface

imperfections, resulting in high values of chloride content. However, as this was also accounted

for in discarding the first layer during the grinding stage of the chioride analysis, the coefficients

were calculated twice, with and without the f k t point, and the analysis that received the highest

r2 was recorded. The value used for tirne was six hours for each cycles, as this was the amount of

t h e the sarnples were exposed to chloride solutions. During the 18 hours when the sarnples are

not exposed to a chloride solution, the chlondes that have entered the concrete will continue to

ingress into the concrete. This effect was not accounted for in the study.


Chapter 4 - Resuits and Discussion 32

Figures 4.1 and 4.2 illustrate a summary of the chloride profiles for the One-day series

and the Three-day series for Mix 1 ..

+4 Cycbi

*9 Cycles

-t 16 Q C ~ S

O 2 4 6 8 10 12 14 16

Depth [mm]

Figure 4.1: Mix 1 (0.4 wlc, with 25% slag) Chloride Profiles for One-day Cycles

-8-1 Qcb

+4 Cycm

*9Qclru

-c 16 Cycles

+25CycrU

O 2 4 6 8 1 O 12 14 16

Depth [mm] - -- - - - - - -- - - - - - -

Figure 4.2: Mix 1 (0.4 wlc, with 25% slag) Chloride Profiles for Three-dny Cycles



It can be seen from the profiles that the Three-day cycles resulted in a higher apparent

sorption coefficient, chlonde concentration, and depth of chloride ingress into the

concrete. The depth of chioride ingress was defined as the depth at which a chloride

content of 0.1% by mass of concrete was obtained

With a more carefiil examination of the coefficients shown in Table 4.3, it can be seen

that the diffusion rate for the Three-day cycles, are approximately twice the value for the

One-day cycles, and that the penetrations are greater for the corresponding number of

cycles within the Three-&y senes. For exampie the specimen that was exposed to 25

One-day cycles has a Sa = 16.17 x IO-'* m2/s with a depth of penetration of 5.6 mm, while

the corresponding specimen in the Three-&y series had a Sa = 32.03 x 10 '" m2/s and a

depth of penetration of 8.5 mm. This shows that the Three-day cycled sarnples produced

sorption rates that were roughly twice as fast and had a greater depth of penetration.

Table 4.3: Mir 1 (0.4 w/c, with 25% slag) Chloride Profile Characteristics

# of

4.3.2 Mix 2

Figures 4.3 and 4.4 surnmarize the chloride profiles for the One-day and Three-day cycles

for Mix 2.

Cycies

1

4 9 16

Cyclic Wetting and Dryiog and its Effects on Chloride Ingress in Concrete

One - Day sa x 1 OIZ CO ? Depths

Three - Day 1

Sa x 1 012 CO ? Depths

m2k Oh CI' mm 42.96 0.44 0.993 1.7

23.22 0.36 0.997 2.2 23.08 0.33 0.999 3.1 28.20 0.33 0.994 4.6

m2/s Oh CF mm

122.82 0.26 0.937 2.0

77.89 0.33 0.999 3.8 33.21 0.45 0.998 4.4 40.92 0.43 0.998 6.3


Depth [mm]

~ i & r e 4.3: Mix 2 (w/c 0.4,25% Slag, 8% SF) chloride Profiles for One-day Cycles

O 2 4 6 8 10 12 14 16

Depth [mm]

~ i & r e 4.4: Mix 2 (wG 0.4~25% Slng, 8% SF) Chloride Profles for Three-day Cycles

From an initial inspection of the chloride profiles for MU( 2, it cm be seen that there was

an increase in chloride penetration. With a more detail examination of the diffusion

coefficients in Table 4.4, it can be seen that the increase in sorption is to a lesser degree

Cyclic Wetting and Drying and its Effects on Chloride ingress in Concrete

Chapter 4 - Results and Discussion 3 5

than Mix 1, as seen for the samples exposed to 25 cycles of wetting and drying in the One

and Three days series. This illustrates that as concretes of higher quality are tested, the

increase in drying time has a reduced effect. This trend was venfied in the results for Mix

3.

Table 4.4: Mix 2 (w/c 0.4,25% Slag, 8% SF) Chloride Profile Characteristics

#of

4.3.3 Mix 3

Figures 4.5 and 4.6 summarize the chloride profiles for MU( 3. It can be seen that the

chloride profiles fiom the One-day series are very sirnilar to the conesponding profiles

fiom the Three-day series.

cycles 1

O 2 4 6 8 10 12 14 16

Depth [mm] - .- - - - - - - - -

~ig&re 4.5: MG 3 (wlc 0.3,25% Slag, 8% SF') Chloride Profiles for One-day Cycles

One - Day Sax1012 CQ ? Depths

- - - - - - -


Three - Day l

Sa x 10" CO ? Depths

m2/s % CI' mm 56.82 0.21 0.993 1.1

m2/s % CI- mm 75.1 O 0.19 0.997 1.1


O 2 4 6 8 10 12 14 16

Depth [mm] - --

Figure 4.6: MU 3 (wfc 0.3,25% Slag, 8% sF) Chloride Profdes for Three-àay Cycles

Although the specirnens in the Three-day series were dried for 66 hours instead of 18

hours in the one-day series, allowing it more than three times as long to dry, it did not

increase the rate or depth of chloride ingress. It would seem the low w/c of Mix 3

combined with the addition of silica fume has lower the rate of drying to a significant

degree.

The numericd results in Table 4.5, show more clearly that the difference in profiles from

the One-day and Three-&y series are negligible. For example the sample exposed to 25

One-day cycles has a Sa = 3.02 x 10 -12 m21s, and a depth of penetration of 2.7 mm, were

vimially identical for the sorption rate, with only a slightly greater depth of penetrations

compared to the sample exposed to 25 cycles in the Three-day series.

- - -

CycIic Wetting and Drying and its Effects on Chloride Ingress in Concrete


Table 4.5 Mix 3: Chloride Profile Characteristics

#of

4.3.4 Drying Period for High Quality Concretes

From the results of Mixes 1, 2, and 3, it can be seen that extending the drying penod has

varying effects depending on the quality of the concrete. High quaiity concretes which

have a finer pore structure need more tirne, or more severe drying to achieve similar

moishire losses. Figures 4.7,4.8, and 4.9 clearly show that with each successively higher

quality concrete, that extending the penod of ârying has a reduced effect.

~ y c i e s 1 4 9 16

Number of Cycles .- - - . . . . . -- - -- - - - - - . . - - - - - - - - Figure 4.7: Mir l(wlc 0.4,25% Slag) Sorption Coefficient vs Number of Cycles

One - Day sa x 1012 CO ? Depths

- -


T hree - Day 1

Sa x 10" CO ? Depths

m2/s Oh Ci- mm 16.26 0.40 0.995 1 .O 9.49 0.52 0.996 1.7 6.35 0.65 0.992 2.2 5.29 0.59 0.997 2.6

rn2/s % CI' mm u

35.58 0.15 0.992 0.6 10.28 0.45 O. 998 1.6 7.52 0.59 0.997 2.4 5.29 0.84 0.997 3.0

Chapter 4 - Resdts and Discussion 38

Number of Cycles

Figure 4.8: Mix 2(w/c 0.4,25% SI&, 8% SF) sorption coefficient vs Nurnber of Cycles

- in

cc-

€ 1, N

k * 2 B O -

Number of Cycles - - - - - - - - - A -- - - . -- - -. -

Figure 4.9: Mix 3(w/c 0.3,25% Slag, 8% SF) Sorptioo coefficient vs Number of Cycles



4.4 Cyclic Wetting and Drying with Distüled Water

To examine the effects of the annual spring rains, some samples were subjected to 25 cycles of

sait water exposure followed by a number of cycles with distilled water. Samples were exposed

to either 4,9 or 25 cycles with distilled water and designated PW4, PW9 and PW25.

The apparent sorption coefficients, surface concentrations and depths of penetrations were found

in the same fashion as described in Section 4.2. Al1 chlonde profiles, and predicted profiles, c m

be found in Appendix C.

tt can be seen in Figure 4.10, there were noticeable decreases in chloride concentrations for al1

samples that were cycled with distilled water. In fact, there is a distinct bend in the profile for

sample PW25. At the depth of bending (4.0 mm), the profile also crosses the chlonde profile for

the sample that experienced no cycles with distilled water (control sample). The concrete fiom

the surface to this point of bending ('idection point'), shows that the chloride concentrations

have decreased while the concentrations beyond this point have a slightly higher concentration.

+No wcycles

-4 W Cycles

-h- 9 W Cycles

4 - 2 5 wcyclss

Depth [mm] -- - - . - - -- - -

Figure 4.10: Mir 1 (0.4 WÏC, 25% sl&) Chloride Profiles for cycle&ith Distilled Water



It would seem that the concrete between the surface and the depth of the 'inflection point' may

have a pore structure that readily d o w chlorides to flow in and out of the concrete. It is well

documented that the outer layer of concrete (the concrete skin) has material properties that are

different than the bulk of the concrete. Kreijer [1984] M e r identifïed this outer layer, but

subdividing it into layers called the cernent skin (approximately 0.1 mm) and the rnortar skin

(approximately 5 mm). However, it is likely that a homogenous matenal would also display

similar behaviour at the outer layer of the concrete, as the concentration gradient was reversed by

applying cycles with distilled water. Additional testing would be oeeded to determine if the

'inflection point' is due to a change in the pore structure at the outer surface, or due to the cycles

with distilled water. This point was used for estimating the mass of chlorides that were released

from the specimens that experienced cycles with distilled water. For M x 1, this 'inflection

point' occurs at a depth of 4.Om.m.

in Mix 2 the specimens that expenenced cycles with distilled water, showed a much smaller

decrease in chloride concentrations. Although there was no particular bend in any of the

specimens in this series, a note was made of the depth where the chlonde profiles of sample

PW25 crossed the profile of the control sample. For Mix 2, this depth occurred at 3.3rnm and

can be seen in Figure 4.1 1.

The chloride profiles of Mu< 3 in this series showed negligible separation nom each other.

However, a measure was made of the 'inflection point' where sarnple PW25 crossed the control

sample, and this occurred at a depth of 1.5 mm, and c m be seen in Figure 4.12.

At the conclusion of these tests, water samples were taken of the distilled water that the samples

had been cycled in, using the same titration method described in Section 3.5.3. With the known

chloride concentration, and the volume of water, the mass of chlorides released into the water

was detennined. A s m d reduction in the volume of water was assumed for losses that would

result during each cycle (the volume of water was assumed to be 1.45 L).



4 No W Cycks

4 W Cydes

-ti- 9 W Cydes

2 4 6 8 10 12 14

Depth [mm]

Figure 4.11: MU 2 (w/c 0.4,25% Slag, 8% SF) Chloride Profiles for Cycles with Water

Figure 4.12: Mix 3 (w/c 0.3,25% Slag, 8% SF) Chionde Profiles for Cycles with Water

- -



Table 4.6 Mass of Chiorides Released

Mars of Ct re1eased Mass of Ct fowtd Dzfference

fiom Samples [g] Nt the Water [gl

Mix 1 (0.4 w/c 25% Slag)

Mix 2 (0.4 w/c 25% Slag, 8% SF)

Mix 3 (0.3 w/c 15% Slag, 8% SF)

It was noted that as less chlorides were released fiom the sample, the mass of chlorides in the

water did not drop correspondingly at the same rate. After some examination, it becarne apparent

that there was a baseline ciifference of chiorides, of approximately 0.13g. One possible cause of

this would be that chlorides had corne in contact with the sample fiom the exposure received

during the cycling process and had entered the water. This amount of chiorides is equivalent to

approximately 90 - 100 ppm of chlorides. in tests perfomed in the lab it was found that tap

water alone has a chloride concentration of 60 ppm. Therefore in view that both the salt cycled

specimens and the water cycled specirnens were dried in the same lab environment, this is a

reasonable explanation.

4.5 Diffusion

The diffusion tests produced chloride profiles that were analyzed using the same approach as the

cyclic testing. The profiles were examined visually and fiom a numerical perspective. Four pairs

of samples, expenenced the following exposure:

1. 120 days immersed in 1 .O molar salt solution, immediately after 28 days of curing,

2. 24 hours of drying in the enclosed chamber, followed by 1 19 days immersed in 1 .O

molar salt solution exposure,

3. 72 hours of drymg in the enclosed chamber followed by 117 days immersed in 1 .O

molar salt solution exposure,

4. 365 days immersed in 1 .O molar salt solution, immediately after 28 days of curing.

Figures 4.13, 4.14, and 4.15 summarize the chloride profiles of the diffusion tests for the three

mixes.

Cychc Wetting and Drying and its Effects on Chloride Ingress in Concrete


O 5 10 15 20 25 30

Depth [mm]

Figure 4.13: Mix 1 (0.4 WC, 25% slag) Diffusion Profiies

5 10 15 20 25 30

Depth [mm] - - - - - ---- -

~igure 4.14: Mir 2 (w/c 0.4,25% Slag, 8% SF) Diffusion Profiles

Cyclic Wetting and Drying and its Effects on Chioride Ingress in Concrete

Chapter 4 - Results and Discussion LW

5 10 75 20 25

Depth [mm]

Figure 4.15: Mix 3 (wk 0.3,25% Slag, 8% SF) Diffision Profiles

It can be seen that the overall d i f i i o n process was virtually identical for the first three types of

exposure, with the one year exposed sample obviously yielding higher chloride concentrations,

and deeper penetrations depths. Table 4.7 shows the diffusion coefficient obtained and the

estirnated depth penetrations. From this information it can be seen that the One and Three day

controlled relativity humidity dryïng had virtually no effect with respect to the 120 days of

immersion in salt solution, in tenns of ciifEsion rates and surface chloride concentrations.

It would appear that there was a slight increase in depth of penetration, in terms of the depth that

the background chlorides are located. This may be attributed to the fact that the drymg cm

provide an initial pull of the chlorides into the concrete. Once saturation has occurred, the

diffusion process controls the ingress, and thus the d i f i son rates will not change. However,

when the depth of penetration is dehed as the depth where a concentration of O. 1% is obtained,

this trend of increased depth with increased drying is not found as shown in Table 4.7. Overall,

the effect of drying did not appear to have a significant effect on the chioride profile, which is

surpnsing when comparing the amount of chloride ingress with only one cycle. More research

Cyclic Wetting and Dryhg and its Effects on Chloride Ingress in Concrete


will be need to be completed to determine the significance of partially drying samples before

difksion tests.

For al1 three mixes it was noted that triplhg the tirne of exposure fiom 120 days to one year

causes the diffusion rates to decrease by a factor very close to = 1.7, and was s h o w for al1

three mixes. A decrease in the diffusion coefficient can be expected, as diffusion decreases with

tirne, because of continued hydration in the concrete.

Table 4.7 Diffusion Characteristics

Condition 120 Days

1 DC.. 119D 30C. 1170

365 Davs

W/C 0.3, 25% Slag. 8% SF

As it can be seen fiom al1 the d i f i i o n rates given in Table 4.7, that the diffusion rates are

changing with tune, as the concrete continues to hydrate. Liitially the diffusion rates are at its

highest, and as tirne reaches infinity, the d i fb ion will stop and become zero, as a condition of

steady state would have been reached. Currently it is not possible to detemiine the diffusion rate

at a particular point in tirne, but an equivalent diffiison rate is given that will yield the sarne

chionde profile in the prescnbed period of time.

4.5.1 Diffusion with Washout

Three additional pairs of samples were exposed to 120 days in 1.0 molar salt solution

followed by various period in distilled water, to examine the extent to which chlorides

will diffuse out of the specimen. Samples were immersed for 30, 60 or 120 days of

distilied water, and designated B W30, B W60 or B W 120 respectively.



O 5 10 15 20 25 30

Depth [mm]

Figure 4.16: Mix 1 (0.4 w k , 25% slag) - Diffusion Profiies with Washout Period

Figure 4.16 illustrates the results f?om Mix 1. A distinct bend can be seen for al1 three

chloride profiles that were exposed to a period of time to distilled water. The 'inflection

point' was taken as the depth where the chloride profile of BW120 crossed with the

chloride profile for the 120 day diffusion sample. This 'inflection point' occurred at 7.6

mm for M i . 1.

The results for MU< 2 are show in Figure 4.17. In this case only sarnples BW60 and BW

120 displayed a discrete bend in their chloride profile, although al1 three samples showed

a marked decrease in chforide concentration. The 'infiection point' for M i x 2 occurs at

6.0 mm.

Figure 4.1 8 shows the diffusion results for Mix 3. Here only sample B W 120 has a bend

in its profile. The 'inflection point' for Mix 3 occurs at 3.8 mm. For ail three mixes it

cm be seen that the chloride concentration increase slightly at depths beyond the

'inflection point'. These resuits show that the existing chlorides already in the sarnples

were continuhg to diffuse. Table 4.8, which is caiculated for oniy the portions after the

' inflection point, ' shows the di f i i o n characte ristics in numerical form.



5 10 t5 25 M

Depth [mm]

Figure 4.17: Mix 2 (w/c 0.4,25% Slag, 8% SF) Diffusion Profües with Washout Period

Depth [mm] - - - - - - - - - - - - - - - - - - - -

~ i & e 4.18: MU 3 (wk 0.3,25% Siag, 8% SF) Diffusion ~ r o N e s with Washout Period



Table 4.8 Difision Charactenstics for Washout Series L

1 30 Days H20 1 3.83 0.51 0.988 12.0 1 1.34 0.48 0.995 6.8 1 0.92 0.38 0.991 4.8

Exposure Condition

ODaysH,O

(120 Days H,OI 4.88 0.45 0.998 12.3 1 2.10 0.42 0.997 7.9 1 1.20 0.35 0.997 5.4

Note: Da values were calculated only for the portions of the profile d e r the inflection

Mix 1 W/C 0.4,25% Slag

DRxld2 Co Depth m2/s %Cr P mm 3.46 0.43 0.990 10.4

point (depth > 7 mm, 6 mm, and 4 mm for Mixes 1,2 and 3 respectively)

During the washout portion of the diffusion testing, water samples were taken once a

week to determine the amount of chlondes that had diffused out of the specimens. Figure

4.1 9 clearly shows that with tirne the chlorides are linearly ciiffushg out of the specimens.

The total mass of chlorides ia the water was estimated based on the results of these water

samples. The area between the chlonde profile for BW 120 and the 120 day diffusion

samples were found to estirnate the mass of chlorides released. These estimates were

very close, verifjhg a conservation of mass was maintained withlli experimental error.

These results are shown in Table 4.9.

Mix 2 w/c 0.4,25% Slag, 8% SF

Dax 1012 C, Depth 1 s %Cr ? mm 1.42 0.48 0.995 7.0

- - . . . - . -- - - - - - - - - - - -- - - - - - - - .- - -- - . .- . -- - - . . . - -

Figure 4.19 Chlondes Released During Washout

Mix 3 w/c 0.3.25% Slag, 8% SF

Da x 1 012 Co Depth d s % CI P mm 0.74 0.45 0.991 4.5

Cyciic Wetting and Drying and its Effects on Chlonde Ingress in Concrete


Table 4.9 Mass of Chlondes Released

1 Mass of Ct relearedfiom Mers of Ct found

Mix 1 (0.4 w/c 25% Slag)

Diffusion properties are similar in al1 directions, as this is depending on the material

properties of the concrete. However, the driving force in dinusion, is the difference in

concentration between the two given points. Diffusion of chlorides will continue as long

as there is a state of saturation, and a concentration gradient.

Samples fd in the Water [g] 0.32 0.33

Mix 2 (0.4 w/c 25% Slag, 8% SF) Mix 3 (0.3 w/c 25% Slag, 8% SF)

4.6 Sorptivity

Sorptivity tests were perfomed on three samples that were dried for one day and another three

samples that were dried for three days in the enclosed chamber. Results for tests that achieved r'

> 0.85 were accepted, and an average was found of these sorptivity values for the specified

conditions. The results are shown in Table 4. IO, and sorptivity graphs for al1 tests can be found

in Appendix D.

0.18 0.22 0.13 O. 12

It was found that the r2 for the sorptivity tests were very low, due to the mild drying in the

chamber. However, it was found that the results obtained sewed to reinforce the fmdings of the

cyclic and diffusion tests. Mix 1 showed a clear hcrease in sorptivity values of the specimens,

while Mix 2 showed smaller increases. The results fiom Mix 3 samples, dried for three days

compared to one day, indicate that increasing the drying time had no effect.

Cyclic Wetang and Drying and its Effects on Chloride Ingress in Concrete


Table 4.10 Sorptivity Results

1 1 Mix 1 1 Mix 2 1 M x 3 1

4.7 Predicting the Rate of Chloride Ingress

I

Having completed this study of cyclic wettiog and drymg, it was hoped that some idormation

could be gleaned to help irnprove exiçting service life models. Through examination of various

w/c 0.4,25% Slag

possible relationships between the number of cycles and the depth of chlotide ingress, there

appears to be a good relationship for depth vs the square root of the number of cycles as shown in

Figures 4.20, 4.21, and 4.22 at least for depths between O - 10 mm of cover. The depth of

w/c 0.4, 25% Slag, 8% SF

penetration to 0.1 % chlorides was used for this analysis following McGrath [ l996].

wlc 0.3,25% Slag, 8% SF

- 3-ûays

- + - 1-Day Fredktsd 11'2 = 0.982)

- - -a - - 3-Dsy Redi~tsd (12 = 0.971)

. - .

Square Root of the Number of Cycles - - - - . . - - - -. -- ---p. .

Figure 4.20: Mir l(w/c 0.4,25%Slag) Depth vs Square Root of the Number of Cycles

Cyclic Wetting and Drying and its EfCects on Chloride Ingress in Concrete


Figure 4.2 1: Mix 2(wk 0.4,

- -

2.0 3.0 4.0 5.0 6 0

Square Root of the Number of Cycles

25%~la& 8% SF) Depth vs Square Root of the Number of Cycles

Square Root of the Number of Cycles

Through conducting a linear regession of ail these points, it was found that the 8 > 0.95 in each

case. This shows that there is potential for modeling the effects of cyclic wetting and dryïng, and

Cyciic Wetting and Drying and its Effects on Chloride Ingress in Concrete


incorporating these effects into service life models. A prediction was made on the number of

cycles needed through extrapolation, to reach a depth of 1 Omm and are shown in Table 4.1 1. The

fact that the depth of penetration is related to the square root of the number of cycles is quite

logically as sorptivity and diffusion is a fiinction of the 4% and cyclic wetting and drymg is

govemed by sorptivity and diffusion.

Table 4.1 1: Predicted Number of Cycles to Reach a Chloride Content of 0.1% at 10 mm

1 N d e r of One-Day Cycles fimber of nree-Day

Further study is needed to increase the scope of this model, as the effect of cycling will have a

Mix 1 (0.4 w/c 25% Slag) Mix 2 (0.4 w/c 25% Slag, 8% SF) Mix 3 (0.3 w/c 25% Slag, 8% SF)

reduced effect at greater depths. For the most part, concrete below 10 mm will remain saturated,

to reach Rebar Cycles tu reach Rebar 90 40 190 110 440 200

and only severe drying conditions would change its moisture state, and therefore the controlling

mechanism will be diffusion, below IO mm.

Cycüc Wetting and Drying and its Effects on Chloride Lngress in Concrete

5.0 Conclusions and Recommendations

5.1 Conclusions

Cyclic wetthg and drying tests can be viewed for the most part as a test of sorption cycles.

At any partially saturated condition, sorption is the goveming rnechanism until a state of

saturation has occurred, at which time diaision becomes the controlling mechanism in the

surface layers of the concrete.

For different types of concrete, varying time lengths are required to achieve a state of

saturation. Although in reality for low w/c concretes, a true state of saturation is dificult to

obtain.

Wetting and drying cycles with Three-day drying penods accelerate chloride penetration due

to capillary sorption, more than One-day drymg cycles, by a factor ranging fiom 1.8 to 2.4,

for the three concretes tested.

As sorptivity and diaision are related to the d G , and these two mechanism governs the

effects of cyclic wetting and drying, it is reasonable that cyclic wetting and drying would also

be related to J K , as was shown in the results.

The rate of penetration of the chloride fiont was found to be linearly related to the square root

of the number of cycles of wetting and drying at least in the outer 10 mm of cover.

The rate of sorption, the sorptivity is govemed by the pore structure of the concrete and its

moisture content. However, spec iwg a penod of tirne for dryhg, given the drying

condition will not provide a constant moisnire content for al1 concretes.

As the rate of saturation is dependent on the pore structure of the concrete, so is the rate of

d ry43

Wetting and dryhg cycles with fkesh water on previously chloride exposed concrete showed

that the chiondes near the surface are washed out of the concrete. The quantity and depth of

chiorides removed increased with the number of fiesh water cycles. Chlorides at greater

depths continue to diffuse inwards during fkesh water cycles.

Chapter 5 - Conclusions and Recommendations 54

5.2 Recommendations

1. The results of the experimentai program show obvious CO-relations between increased

number of cycles and increased depth of chloride penetration. Extending this experimental

program for a greater number of cycles would provide information for estimahg the number

of cycles required for threshold level chlorides to reach steel reinforcement.

2. ïhe primary mechanisms of cyclic wetting and drying are diaision and sorptivity. What

detemiines the goveming mechanism is the hygrometric state of the concrete. Therefore it is

irnperative that the moisture condition be known as accurately as possibie. This can be

achieved by monitoring the mass of the specirnens during cycles, and later determinhg the

moisture content or perhaps through measuring the surface relative humidity. Since an

accurate mesure of the moisture content cannot be made non-destructively, a relationship

needs to be established of the rate of moisture lost under defmed environmental conditions, in

partner with ongoing tests.

3. During sample preparation for sorptivity testing, the amount of moisture lost fiom saturation

to the prescribed moisture conditions should be monitored. With this information, the

amount of water required to create a saturated sample would be known. The sorptivity test

codd then be continued until a state of saturation has been achieved. The information

provided by extending the testing penod may suggest how the transition fiom sorption to

diffusion occurred.

Cyclic Wetting and Drying and its Effects on Chioride Ingress in Concrete

6.0 References

Abdul-Hamid, ACTayyib, J., Al-Zahrani, M. M., 'Use of Polypropylene Fibers to Enhance Deterioration Resistance of Concrete Surface Skin Subjected to Cyclic Wet/Dry Sea Water Exposure,' AC1 Materiais Journal v87, n4, July-August 1990, pp363 - 370.

Ben& E. C., Evans, C. M., Thomas, M. D. A., 'Chloride Diffusion Modeling for Marine Exposed Concretes,' in Page, C. L., B d o r i h , P. B., Figg, I. W., (Editors), Corrosion of Reinforcement in Concrete Comiruction, Royal Society of Chernistry Thomas Graham House, Science Park, Cambridge, 1996.

Berman, H.A., 'Determination of Chloride in Hardened Portland Cernent Paste, Mortar, and Concrete,' Journal of Materials, v7, n3, September 1972, p330 - 335.

Cran., J., 'The Mathematics of Diffusion,' Oxford University Press, Oxford, 1975.

Crumpton, C. F., Smith, B. J., Jayaprakash, G.P., 'Salt Weathering of Lirnestone Aggregate and concrete Without Freeze-Thaw,' Transportation Research Record n 1250, 1989, p8 - 16.

DeSouza, S. J., 'Test Methods for the Evaluation of the Durability of Covercrete,' Masters Thesis, University of Toronto, Ontario, 1996.

Escalante, E., Ito, S., 'Measuring the Rate of Corrosion of Steel in Concrete,' ASTM Special Technical Publication n1 O65 August 1990, p86 - 102.

Hall, C. and Tse, T. K., 'Water Movement in Porous Building Materials - W. The Sorptivity of Mortars,' Building and Environment, v2 1, n2, 1986, p 1 13 - 1 1 8.

Hall, C. and Yau, M.H.R., 'Water Movement in Porous Building Materials - D<. The Water Absorption Sorptivity of Concretes, 'Building and EnWonment, v22, n 1, 1987, p77 - 82.

Hall, C., 'Water Sorptivity of Mortars and Concretes: A Review,' Magazine of Concrete Research, v41, n147, Iune 1989, p5 1 - 61.

Hooton, R. D., Mesic, T., Beal, D. L., 'Sorptivi@ Testing of Concrete as an Indicator of Concrete Durability and Curing Efficiency,' Proceedings, Third Canadian Symposium on Cernent and Concrete, Ottawa, Ontario, August 1993, p 264 - 275.

Hooton, R. D., 'Review of Deterioration Mechanîsms,' University of Toronto CIV 1252 Course Notes, 1995.

Chapter 6 - References 56

Hootoo, R. D. and McGrath, P. F., 'Issues Related to Recent Developments in Service Life Specifications for Concrete Structures,' University of Toronto, Ontario, 1995, 10 pages.

Kosmatka, S. H., Panarese, W. C., Gissing, K. D., MacLeod, N. F., 'Design and Control of Concrete Mixtures, Sixth Canadian Edition,' Canadian Portland Cernent Associaion, Ottawa, Ontario, 1 995.

Kreijger, P.C., 1984, 'The Skin of Concrete - Composition and Properties,' Matériaux et Constnictions, v 17, n 100, p275 - 283.

Maclmis C. and Nathawad Y.R., 'The Effects of a De-king Agent on the Absorption and Permeability of Various Concretes.' in Sereda P.J. and Litvan G.G. (Editors), Durabiliiy of Building Materials und Components, ASTM Special Technicai Publication No. 69 1. 1980, p485 - 496.

Mailvaganan, N. P. 'Repair and Protection of Concrete Structures,' CRC Press, 1992.

McCarter, W. J., Ezirim, H., Emerson, M.,. 'Absorption of Water and Chioride into Concrete,' Magazine of Concrete Research, v4, n 158, March 1992, p3 1 - 37.

McCarter, W. J., ' Assessing the Protective Qualities of Treated and Untreated Concrete Surfaces under Cyclid Wetting and Drying,' Building Environment, v3 1, n6, 1996, p55 1 - 556.

McCarter, W.J. and Watson, D., 'Wetting and Drying of Cover-Zone Concrete,' Proceedings of the institute of Civil Engineers - Structures and Buildings, v122, Issue 2, May 1997, p227 - 236.

McGrath, P.F., 'Development of Test Methods for Predicting Chloride Penetration into High Performance Concrete,' PhD Thesis, University of Toronto, Ontario, 1996.

Moukawa, M., 'Deterioration of Concrete in Cold Sea Waters', Cernent and Concrete Research, v20, n3, May 1990, p439 - 446.

Neville, A. M., Properties of Concrete Fourth Edition, New York, NY USA, 1996.

Parrott, L.J., 'Moisture Conditioning and Transport properties of Concrete Test Specimens,' Materials and Structures, v27, n 1 72, 1994, p460 - 468.

Parrott, L.J., 'Water Absorption, Chloride ingress and Reinforcement Corrosion in Cover Concrete: Some Effects of Cernent and Curùig,' in Page, C. L., Barnforth, P. B., Figg, I. W., (Editors), Corrosion of Reinforcement in Concrete Consîruction, Royal Society of Chemistry, Thomas Graham House, Science Park, Cambridge, 1996.

Pollock, D., 'Are Concrete's ILls Fully Underdstood?' Civil Engineering, July/August 1988, p36 - 37.


Chapter 6 - References 57

Selih, J., Sousa, A. C. M., Bremner, T. W., Moisture Transport in uiitially Fully Saturated Concrete During Drying,' Transport in Porous Media, v24, ni, 1996, p8 1- 106.

Tang, L., and Nilsson, L-O., 'Chloride Binding Capacity and Binding Isotherms of OPC Pastes and Mortars," Cernent and Concrete Research, v23,n2, 1993, p247 - 253.

Thomas, M. D. A., 'Course Notes nom Repair and Maintenance of Concrete Structures,' University of Toronto, 1995 and 1997.

West, R.E., and Hirne, W.G., 'Chloride Profiles in Sdty Concrete,' Matenal Performance, v24, n7, Iuly 1985, p29 - 36.

Yeomans, S. R., 'Performance of Black, Galvanked, and Epoxy-Coated Reinforcing Steels in Chloride Contaminated Concrete,' Corrosion, v50, nl , January 1994, p72 - 8 1.

Young, J. F., 'Humidity Control in the Laboratory using Salt Solutions - A Review,' Journal of Applied Chemistry, v 17, September 1967, p24 1 - 245.


Appendix A - General Data AI

Chemical Analysis

SiO,

A1203

Fe203

Ca0 Mg0 LSO,

K20 Na20 Ti02

P2°5

Mn203

Sr0 LOI

l

Total

Portland Cernent Slag Silica Fume

Cyciic Wetting and Drying and its Effects on Chlonde Ingress in Concrete

Appendix A - General Data A2

Batch Record Sheet Mix #I - 0.4 w/c, 25% Slag

1 1 Volume/each Volume I( 1 1 Nurnber [Litres] [Litres]

Cylinders 8 1.65 13.2 Slab (250 x 350 x 75) 8 6.88 55.1

1 Totai Volume 68.2

~IFINE AGG ABS (%) 1 1.4 11

IIMIX NO. la II

MATEEUAL

Porüand Cernent - Woodst. Type 10

Fïy Asb - Ft. Martin Slag - Standard

Siiica Fume - SKW Beancour

Coarse ~ggregatc-~ufferin 10 mm

Fie Aggregate - Nelson

Cyclic Wetting and Drying and its Effects on Chlonde Ingress in Coacrete

Water Redacer 25 XL (mY1ûûkg) Superplasticizer - SPN (dlûûkg) Air Enlrainer Micro Air (mülûûkg) Air Content (%)

Tot&: Mass =

iwater 150.0 1 1000 10.i01

~~HEORECTICAL BATCH QUANTITIES

325 480 45 7.0

2287.9

MASS

(kg)

285 0 95 0

1100 654

BATCH QUANTITIES

Batch

Org)

22.79 0.00 7.60 0.00 87.96 52.29 11.99

1200 1200 1200

yield (m.3) =

DENSITY

Wm3) 3 150 23 00 2920 2200 2670 2700

CORR

Org)

88.06 53.80 10.39

VOL

W) 0.0905 0.0000 0.0325 0.0000 0.4 120 0.2422

0.00 12 0.00 18 0.0002 0.0700 1 .O005

145.8

182.9


Batch Record Sheet M i s #2 - 0.4 wfc, 25% Slag, 8% Silica Fume

II II Volume/each Volume 11

((BATCH SIZE (litres) I 85II

1 1 C y linders

Slab (250 x 350 x 75)

1

Number [Litres] [Litres] 8 1.65 13.2 8 6.88 55.1

Total Volume 68.2 -

NO. 2 II COARSE AGG MC (Oh)

FINIE AGG ABS (%)

FINE AGG MC (%)

TaEORECTICAL BATCH QUANTITIES

MASS DENSITY VOL

2.0 1 1.4

4.15

Portland Cernent - Woodst. Type 10 255 3150 0.08 1 0 21.66 Fiy Ash - Ft. Martin O 2300 0.0000 Slag - Standard 95 2920 0.0325 Silica Fume - SKW Eeancour 30 2200 0.0136


Coarst Aggregate-Dufferin 10 mm 1100 2670 0.4 120 Fit Aggrcgate - Nelson 642 2700 0.2378 Water 150.0 1000 0.1500 Water Reducer 25 XL (d100kg)

Superplasticizer - SPN (d100kg) Air Entrainer Micro Air (mi/lOOkg) Air Content (%)

To tals: M a s =

325 645 40 7.0

2276.6

1200 1200 1200

yield (m3) =

0.0012 0.0025 0.0002 0.070 1 1 .O008

104.9 208.2 12.9

193.4 i

Appendix A - Generai Data A4

Batch Record Sheet Mix #3 - O 3 W/C, 25% Slag, 8% Silica Fume

-

C y Iinders Slab (250 x 350 x 75)

Volume/each Volume Number [Litres] [Litres]

8 1.65 13.2 8 6.88 55.1

BATCH SIZE (litres) COARSE AGC ABS ( O h )

~~MTEA R ~ U 1 MASS 1 DENSITY 1 VOL II Bitch 1 CORR

1.67 COARSE AGG MC ( O h )

FINE AGG ABS (%)

FINE AGG MC (%)

(kg) ww (m3) (kg) Ocg) Portland Cernent - Wooâst. Type 10 308 3 150 0.0978 26.14 Fiy Ash - Ft. Martin 0 2300 0.0000 0.00 SIag - Standard 115 2920 0.0394 9.76 Silica Fume - SKW Beancour 37 2300 0.0 168 3.14 Coarse Aggregate-Dufferin 10 mm 1100 2670 0.4 120 93.36 93.83 Fie Aggregatc - Nelson 600 2700 0.2222 50.92 51.73 Water 136.0 1 O00 O. 1360 1 1.54 10.27

1

2.18 1.4

3.01

~ a t e r Reducer 25 XL (m11100kg) 325 1200 0.00 15 126.9 Superplasticizer - SPN (d100kg) 1160 1200 0.0053 452.9 !Air Entrniaer Micro Air (mV100kg) 80 1200 0.0004 Air Content (%) 7.0 0.070 1 Totals: Mass = 2304.6 yield (m3) = 1 -00 1 5 195.6

Total Volume 68.2

Cyclic Wetting and Drying and its Effects on Chloride Ingres in Concrete

Compression Test

Mix 1 - 0.4 w/c 25% slag

7 Days

Specimen 1

Average Specimen 2

Average

Diameter Load Comp. (mm) (W ( M W 101.9 102.1 102.7 102.8 102.4 234.0 28.43

28 Days 91 Days

Specimen 1

Average Specimen 2

Average Specimen 3

Average

Diameter Load Comp.

Specimen 1

Average Specimen 2

Average

Diameter Load Comp. (mm) (W ( M W

1 O3 1 O3

102.8 102.7 102.9 371.2 44.66

Compression Test

Mix 2 - 0.4 wlc 25% slag, 8% SF

7 Days

Sample Specimen 1

Diameter Load Comp.

Average Specimen 2

Average Specimen 3

28 Days 91 Days

Diameter Load Comp.

Specimen 1

Average Specimen 2

- --

Average Specimen 3

Specimen 1

Average Specimen 2

Diameter Load Comp. (mm) (W ( M W 102.6 104.1 102.4 102.9 103.0 486.0 58.33 102.3 103.3 102.5 102.3 102.6 473 57.21


Compression Test

M h 3 - 0.3 wlc 25% h g , 8% SF

7 Days

23-Jd-96 Sample

l

Specimen 1

Average I 1

Specimen 2

Average I I

Specimen 3

Average Total Averagc

Diarneter Load Comp. (-1 (W ( m a ) 101.6 101.7 101.8 101.7 101.7 519.0 63.89 102.1 102.4 104.6 102

102.8 526.0 63.40 101.7 102.4 100.3 100.7 101 -3 484 00.08

28 Days

13-Aug-96 Sample

Specimen 1

Specimen 2

Average Specimen 3

Average

Diameter Load Comp. (-1 (W ( M W 10 1.5 101.6 101.8 103

102.0 654.0 80.08 102

101.8 101.8 101.6 101.8 657.0 80.72 103

101.8 100.9 100.7 101.6 618 76.23

a 79.0 1

Cyciic Wetting and Dryhg and its EfTects on Chloride hgress in Concrete

Appendut B - Test Program BI

Sarnples - Coding System

Svnple is dncd for 24 horirs. and thcn testcd for sorpawty

Replica 2 Replica 3

Sample is dned for 72 horas and ihcn testcd for sorpbwty

Replia 2

Replia 3

Samplc gocs thmugh one 6 houn in salt soluuon 18 hours dry. cycle mi IS thcn profile gnnded

Replia Z Sample goes thmugh four 6 houn in sait solu~on. 18 hours dry, cycles and IS thai pmfilc gnnded

Replica 1 ,ample goes thmugh nine 6 houn in sait solunon. 18 hom dry. cycla and IS thai profile gnndtd

Rcplica 7

sample gocs through 1 6 6 houn in salt wilur~on 18 h o u dry, cyclcs anci IS t h a ~ pmme gMded

Rcplica 2

jmple goes h u g h 25- 6 houn in salt solut~on. 18 ho= dry. cycle and IS thai profile gnnâed

Rcplica 1

iample gocs through 36-6 houn m salt soluiion. 18 houn dry. cycles and IS then pmfilc gnndcd

Rcplica 7

jample goa thmugh four 6 hours in watcr, 18 h o m dry, aftcr 15 salt solunon cyclcs and IS thai profile gnnded Replica Z

ivnplc goes thmugh nine 6 houn m wata. 18 hours dry. aller 25 d t solutron cycles and IS thai pmtile gnndai

Rtpliu 2 iample goes thmugh 25- 6 hours m watcr. 18 hours dry. a&r 3 salt soluuon cycles and IS chai pmfilc gru~ded

Rcphu 1

;ample gots through one 6 hours in salt solution 66 houn dry. cyck and IS hm profile gnndcd

Replica I iamplc g o a through four 6 hours in salt solution. 66 houn dry. cyclcs and u rhcn profile gnnded

Replica 3

iample goa thmugh nme 6 hours in salt solution. 66 hours dry. cycles and is rhm profile gnnded Replica 2

impie gocs through 16-6 hours ui Ylt scilullon, 66 houn dry. cycla and IS then profile gnnded Rcplica 2

h p l e goes thmugh 3- 6 houn in sait solulion, 66 h o u dry. cycles and IS thai protile gnndcd

Reptica 2

8amplc goa Ltuough Il0 days m salt saluuon

Replia 2 ample IS dry for 14 hours ruid ihar iii ut salt soluiion of 119 days

Replia 2

ample IS dry for 72 houn and ihcn is ut salt solutron for 117 days.

Rcplica Z ample goa through 120 days in salt solution and hm 30 days ui ~i;iia

Replia 2

ample gocs thruugh 120 days in saIt solution and thm 60 days III mm Replia 1

ample gocs tbrough 120 days in salt solunon and thcn 120 days m water

Cyclic Wetting and Drying and its Effects on Chloride Ingres~ in Concrete

Appendix B - Test Program B2

- - _--.-. _&!!! - W I L - - - : Tc*-% 1 s 1 19 'lp s & P I ~ $ ~ - - !Jp mak PI(l6Y4 -keK -- - . . -1pn 6i.i. Pl(2j-t - - - - ; : s** - 5 - :9.Ap -& ~ l c i 2 y l r , Pysyi - coJt PICI4y5

JP h m 2 w _ E - 2 o ~ , M , ~ i J e . o r t ! ! L l r X J . -- -- -F ~ P K ~ ~ Y 6 , P W l . F - - - - - E - _ T - 32 -%lp + Pl11 2114 - --- JE^ Pl(I3JQ ,PL T O y f L S 8 i i !ZO ,D 8 1 ( - 2 ~ 1 1 0 , B ~ ) - I ~ E - -- - S I ~ & ~ J L 3 oûp DUU&C ~ I O ! K - 1 W: 43 s ~ p - @ ~ f i ~ t 5 L ~ $ ~ -- 9.-Je d --- Pli l 4 p -% (a_SIaoJ 81(+120 . - - - - - -9dp scalp I Cl ay1


Appendïx B - Test P r o p m B5


Sampk D i b of artndlng Dab of AnalysIr KHI-1P1-1 1O.Sep-ai 1 1 -Sep06 1

WPm Comcbd Corncbd Cr Cr Conbnt SC Pndlcbd Moasunnwnt h p t h Dipth [kpth Conc. (W concnb CI' Conbot

[Inllûûû] [inllOOôJ [inllOOOl [mm] [PW] mrr) X SB1 30 33.0 0.8 3164.2 0 2388 O 2385

W P ~ Comcbd Comcbd Cr WConbnt% Pmdkbd Mmasumnont Dopai Wpth ihptti Conc. (%concnb Cr Conbnt

[infi0001 [InJlOOO] [inllOûO) [mm] IPPm] nusr] X 408 30 21.3 0.5 4881.4 0.4081 0.2858

Note: Firsl point was no1 wed foc calailalmg Re Coeff~dsnts to predict Pis Chlonde Profils

KHI -1 P4-1

00 2 O 4 O 10 1 O IO 0 11 0 1 4 0 10 C

Depth {mm]

Sampk Date of Orindinu Dite of Analyak KHI-1PQ-1 24-Ssp-06 25-Sep-BB 1

1 l k ~ m Comcted Cornclod Cr CrConbnlX Pndkbd 1 1 Morsunmnt lkpth b p t h [kath Conc. I%concnb CI- Conbni 1

410 70 83.5 420 110 1235 388 150 M3.5

190 203 5 Avrnqr 230 243.5

413.5 270 283 5 310 3235

Total h p t h 350 363 5 400 390 403.5

Nols: Fin1 polnl war no1 used lu caidabng the C d i a e n u Io pred~ct the Chlonde Prdllo

Comcbd Comcbd Cr Cî'Content% Prmdkbâ Moa~urmnnt ûopth OIpm Wpth Conc. 1% toncnb C I Content

Note: Fint point was nOl wed for caialating the Codfidenlr to prodicl the Chionde Profils

0 0 2 O 4 0 8 O O O 10 0 12t

Depth [mm]

1 Simnk D8b of Orlndlnm D i b of Anilwlr 1 1 KHI-1~25-1 -

7-0~1-86 8-0c1-88 9-019-û6 1 Diph Comcbd Comcbd CI' CI' ConlrnlK Pndkrd

Mairuremont Chpîh Chpth Lkpth Conc, (W concnb Cf Conbnt IlnJlOWl [mm]

35.5 0.9

Note: Fitst point wai ml useâ fa caicrlabng üw Coetfiasnts to predicî the Chionde ProCile

%mpk D a r of Grkidhg ~rto of Anrlyrb KHI-1P36-1 746 -88 8-0ct.M 8-Oct-W

WP* Comcbd Comcmd Cr Ci'Conmnt% PndlcWd M a a r u m n t Ikpîh OIpm h p l h Cont. (%conenb Cr Canbnl

~InJ1000J [in JI0001 [hJ1000] [mm] tppml man) 'rC SB1 37.5 42.3 1.1 8858.4 0 5943 0.4294

- O 7 0 a m

060

f 050 U C O O h O osa fp g 029 0 L O O 10 E O

000

KHI -1 P25-1

O60 U C O O 4 0

C O or, E 8 020 '0

6 - o 10 C O

000

KHI -1 P36-1

Sampk Ikb of Qrlndlng Ikb of Anrlyalr KHI-1PW4-1 1 1-06-98 19-0d.M 2O.Od-BB

Comcbd Comcbd Cr CC ConbnlX Pndkbd Moisunmrnt Ikpth OIpm Dopa Conc. (Xconcna, Cr Conml

[InJlW] [InJlOûô) (InJlOOO] [mm] bpml m m ) W 600 37 5 285 O 7 5812 2 0 4018 O 3874 59 1 87 5 70 5 2 0 3577 1 O 2880 O 2978 583 1375 1285 33 2Wû8 0 2213 O 2178 594 1875 1795 4 8 2374 4 0 1678 0 1508

237 5 2285 5 8 1770 O 1073 O 0980 Avrnge 287.5 279 5 7 1 1248 3 0 0553 O Ml2

592 337 5 329 5 8 4 811 2 O 0215 0 0356 387 5 379 5 9 6 746 4 O 0050 O 0185

Tob l ihph 437 5 4295 10 9 738 8 0 0040 O 0101 600 487.5 4795 122 733 4 O 0037 0 0048

5375 5295 134 m 00000 O 0022 587 5 5785 14 7 743 O O 0047 OOOOe

Note: Flnl point was no1 used ta dcdabng the Cdicientr 10 ptedct h o CNonde ProTile

mpth C o m c W Comct.d Cr CrConmt% Pndkted Mersurornont üoprh b p t h i h p h Conc. (Xconcnb CC Conlint

[in A0001 [inJlOOo] [InllOOOl [mm] [ ~ P m l mu) % 597 37.5 38.3 1 .O 4807.6 0.4065 0 3282

Note: Fust pdnl was ml used toc cdalaüng tho Cos(liamls to predid me CNonde ProMo

O O 2 O 4 O O O O O 100 12 O 14 O

Depth [mm)

O0 2 O 4 O 6 0 O O 100 12 O

Depth [mm]

b P & C o m c ï d Cornclrd CC CtConïnt% Pndkbd Moimuremnt ihpth Ciopth üopth Conc. [Xconcnl. CTContent

[inJlOOOl IhJlûûû] lin JlOOO] [mm) [ppm] mm) X 704 37.5 43.5 1.1 3240 0.2404 0.3365

Nole: The first 3 polnlr were no1 andyzed

OSQ n * 0 9

I 0 ,

O * 8 g O 3 0

C O 2 5 O

020

g o i s O r, O 1 0 -

00s

om

&mpk D i b a l Grlndlng OIb of Anrtymk KHI-3P1-1 259d-88 26-Ocl-88 1 S, = 1.221E-10 m'lm Ca= 0.2826 % r' = 0.S361

Corncbd Comcbd Cr CTConbntn Pndktad Moisunmont ihp lh Doplh (kpth Conc. (W concnb Cf Conbnl

(înJlOOO] [inllWl [inllOOOl [mm1 IPP) ma.) SL 418 30 38.0 1 .O 2460.6 O 1830 0 1752

h m p k D i b of 011ndlng D i b of Anaiymim KHI -3P4-1 12-NOV-98 3.J~1.07 4-Jiin-87

D@Pa Comcbd Comcbd Cr CrConbntX Pndkbd Moasurninnt mplh h p l h OIpth Conc. (%concnb Cl' Conbnl

[hrlooa] [Inlloool [lnllaoo] [mm] [ppm] n u S i ) X 414 32.5 35.8 0.9 4330.4 03588 0 2650 408 72.5 75.8 1 .9 2742.9 O 1888 0 1878 388 112.5 115.8 2.9 2086 9 O 1342 O 1393 414 152.5 155.8 4.0 1698 3 O 0052 O 0825

192.5 195.8 5.0 1316 6 O 0572 0 0578 Avrngm 232.5 235.8 6.0 1104 O O359 0.0338 408.25 272.5 2758 7 .O 929 1 00184 O 0185

312.5 3158 8.0 825 5 0 0081 0.0085 Total OIpth 352.5 355.8 9.0 OdOOO 0.0045

405 302.5 3858 10.1 772.1 0 0027 00020

Note: Fint poinl was no! used for crdarlating aie C M i a e n t i Io predict h e Chloride Profile

O O 2 O 4 O 6 0 1 0 IO O 12 1

Depth [mm]

1 &mpk D8b of Qrlndlng D i b of Anilysla i ( KHI-3PB-1 12-Nov-98 3-Jan-87 4.Jso-87 j

Comcbd Corncbd Cr Cr Contont X Prodlclrd kasuramont b p t h (kpth OIpth Conc. (SCconcnb CI Conbnt

[InJlOOO) [InJlOOô] IlnJlOOO] [mm] [PW] MI#) X 388 27.5 28 5 O 7 5015 8 O 5072 0 3816 407 67 6 085 1 7 3726 O 2882 0 2853 307 1075 1085 2 8 2821 5 O 1077 O 2012 402 1475 1485 3 8 2134 2 O 1290 O 1334

1875 1885 4 8 1699 2 0 0855 O 0830 Average 227 5 228 5 5 8 1387 3 O 0543 O 0483

401 2675 2685 6 8 11208 O 0277 0 0262 307 5 308 5 7 8 847 3 O 0103 O 0133

Tohl [kpm 3475 348 5 8 0 B89 5 O 0025 O 0082 400 387 5 388 5 B O 00000 O 0027

Nols: FImi point was mt w e d for caldating the Cosffiamts lo prodicl h o Chlorido Profile

I ~h ~ o m c b d ~omctmd ci' Ci'ContontX P M ~ M 1 I llikaruromont ûmth ûaaih ümth Conc. t ~ c o n c n b Cr Con(int I

Note: Fint poinl was no1 usdd fw caladabmg the Cobniamts Io predct aie Chlwids Profile

Depth [mm]

0 0 2 O 4 O e O 4 0 10 0 12 0 1

Depth [mm]

mpfi Corncbd Corncmd Cr Cr Contant% Pndktad Mm8unmnt h p t h I k p h tkpth Conc, (% concnb CI' Conbnt

[ln JlOoo] [lnJlôûO] I inA WO] [mm] Lppml nusr) % 588 32.5 M.5 0.6 6873 5 O 7600 OS446

Note; First pdnl was no1 ussd foc cdiadaung the CosMdmls 10 prediet me Chlonds Profils

KHI -3P26-1

\

Sampk Olb of Orindina D8b of Aru\yrlr KHl-OBlZO-1 OJarr97 17 -J~-87 I

WP* Comcbd Comcbd CF CîConYnlX Pndkbd Maiaunmnt h p t h ûapth h p m Conc. (% concnb CI' Conbnt

[InJIOOO] IinJlOûû] [InJiOOO] [mm] IPPml m.8) X 1033 35 41.0 1 .O 4512.3 03808 O 3875 1027 105 111.0 2 8 1040 175 181 .O 4.6 1044 245 251.0 6 4

315 321.0 8 2 Avrngi 385 381.0 8. 9

1 036 455 461.0 11 7 525 531.0 13 5

Toh lhpth 585 601.0 15 3 1030 665 671.0 170

735 741.0 18 8 875 881.0 22.4 W5 051.0 24.2 1015 1021.0 25.8

Note: Ail points were Mdyzed

Sampk D.m of Grindtng ihb o f h i y r k KHI-9385-1 10-Sep87 13-Sep87 I

I am ~ o m c b d comcted ci' CtConbntX ~ n d k c d 1 w*

[in J I 0001 49.8 78.8 108.8 168.8 319.8 408.8 520.8 048.8 799.8 949.8 1 189.8

Conc.

49- 6388.5 4857.3 3882 1 3454 2 2824.4 1805.4 1388 1 802.4

(% concnta Ci' ConOInl

O 5488 0.4740

Note: Flnl point was not ussd foc cdalating the Codïiasnls to prodicl the Chlonda Prdile

D,= 3AEtSE42 m'la Ce- 0.4286 X += 0 . W

KHI -081 20-1

5 O 10 O 150 200 2s a

Depth [mm]

1 SImpk D i b of Orindlnp Dab of Anrîysls 1

. W P a Comcbd Comctrd Cr CI'ConbntK Pndkbd

Moisunmrnl PIpth OIph (kpth Conc. (%concnb CI Contmt [InllWûl [InAôûOl [inliOOO] [mm] [ppm) miss) %

795 37 5 31 0 O 8 ô428 5 O 5745 0 4231 795 1125 1080 2 7 3958 6 O 3275 0 3434 782 1875 181 O 4 6 3438 5 0 2755 0 2690 802 262 5 256 O 6 5 2848 8 0 2165 O 2031

337 5 331 O 8 4 2361 6 O 1678 0 1475 Avrnpr 412 5 4080 10 3 1690 1 O 1006 O 1029

703 5 487 5 481 O 122 12694 O 0588 O 0688 5625 5560 14 1 1011 8 0 0328 O 0442

Toul OIpth 637.5 031 O 16 O 773 8 00090 0 0272 800 7125 7080 179 9 OûOW O O160

7875 7810 19 8 711 3 O 0028 OOOeO

Note: First pocni was noi used for cdalaîing the C d i d m t s to prodicl me Chionde ProTile

O.P* C o m W Comctrd Cr CTConbntX Pndkbd M.asuronuni Dlpth OIpth b p t h Conc. ( X c o n c n ~ C I Conbnl

linJi 000) [in J i 000) (inJ1000) [mm] ~PP@ mu) X 881 37.5 38.0 1 .O 0445 5 0.5712 0 3W3

I Nole: Fiisl paril was no1 used for dalaring Uie Cooifiaents io predicl the Chioride Profile

0 0 20 40 60 80 100 120 140 160 180 ïûa

Depth [mm]

0 0 20 40 60 80 IO0 120 140 160 180 2ûO

Depth [mm]

1 &mpk Dab of Grlnding D i b of Anahrab 1

WP* Cormcbd Comcbd Cr Cr Contint X Pndkttd Mearunnnnt Dopm Lhpm Depm Conc. (% concnb Cf Conbnl

1 [JnJlOOO] [ln JlOW] [InJlOOO~ [mm] ~ ~ p m l m a i l X 824 37.5 38.8 0.0 4048.1 0.3322 0.4715 825 828 810

Avrnga 824.25

Toial b p t h 825

Note:

1 hm C o m c W Comcbd Cr CTConbntX P n d k b d 1 Moarunnnnt Lhplh Dopa h p l h Conc. (Xconcnb, Cî' Conbnl

[ h J l 0001 [inJlOOq [in JtOOo] [mm] IPpm] mu) % 981 37.5 42.0 1.1 29081 0 2174 O 3817 981 988 888

Avrngm 884.5

T O ~ I h p m 880

Nole:

00 2 0 40 1 0 80 100 110 t40 100 100 ma

Depth [mm]

0, = XH16E-12 m'la Co= 0,4322 X r ' m O.##

KHI -BW60-2

00 2 0 40 80 80 IO0 120 140 180 I B O ZOO

Depth [mm]

I mpm comcbci comcbd Cr CrContmnt% G d k G n Morsur«mnt h p t h [kpth Dmplh Conc. (W concnte CI' Conbnt

~InJlOOO] IinJlOOO] ~InllOOOl [mm] Ippm] mi.) W 898 37.5 38.8 0.g 2581.4 0.1921 0.4162 998 988 979

Avengr 980 25

f o b l (kpth 880

Note: The firrt 5 points m a ml Mdyzed

5 O 10 0 150 200

Depth [mm)

1 WPfi Corncbd Comcbd C t CTConbnlX Pndkbd 1

Average 190

&Pa [in Jl 0001

1 O 30 50 70 80 110 130 150 170 le0

Conc.

(ppm] 1382.2 2171.8 1633.7 1279 3 1085 1 885.8 877 3 788 4 769 3

( X concnb mirs) O.îB39 O. 1429 O.OB91 0.0530 0.0352 O. 0223 0 0134 0.0053 00026 0.0000

M u a u m n t Wpth Dopa k p t h Conc. (Xconcnb Cr Conun1 (bi J10001 [inlloOal [kilt0401 (mm] IPPml mu) %

234 12.5 9.8 0.2 4498.1 0.3800 O. 3824 251 37.5 257 82.5 247 87.5

112.5 Avenga 137.5 247.25 162.5

187 5 Tobl h p t h 212.5

250 237.5

&mpk D i b of Qrlndlng D.b of Afulyais KM-1PQ-1 %May-97 2 Jur-97

-Pa ~or6ct .d Corncbd CC C i ConbntX PndkCd Mainunmrnt h p ü I ihpth [kpth Conc. 1% concnta CI' Conbnt

[in Jl Wû] FJlOOOl IlnJlûûû] [mm] [ppm) mu) I 255 10 8.0 O 2 8844 3 0.6059 O 6076 241 30 250 50 250 70

80 Avrngo 112.5

249 137 5 182.5

Tohl WpüI 187.5 250 212 5

237.5

Ékmpk üaîa of Otindlng D i b o f h l y 8 l r KHz-1P16-1 4 Jin-97 6-dm97 10-Jm-97

Comcbd Comcbrd Cr CrConbmt% Pndkbrd ~ u n n n n t [kpth ûepth lkpth Conc. (W concnb CTConbnt

[kiJlOOOl [InJlW] [InJlOOO] [mm] [ ~ P m l mu) 'IL 536 12.5 18.0 O. 5 7588.4 0.6934 07087 *

Nole: Ail poinls wsre Malyred

O 0 1 O 2 0 3 O 4 O 5 O O 0 70 O 0 O 0 ln0

Depth [mm]

8.1 7.341E-12 mals C o i 0.8422 I - 0.@@27

O 0 10 2 0 J O 4 0 5 0 1 0 70 O 0 O 0 100

Depth (mm]

Comcbd Comcbd Ci' Ci'ConbnIX Pndkbd k i i u n n n n t [kpth Wpth Wpth Conc. (Xconcnta CTConbnt

( (inlrooo] [lnllooo] [ in~ooo] [mm] IPPI ~ S S )

576 37.5 38.8 1 O 5921.8 0.5273 0.5206

Note: Ail pointa wsre d y m d

mpth Comcrd Comcbd Cr Cr ConbntX Pndkbd Miaiunnunt [kpm ihp& Dopa Conc. 1% concirb CI' Conbnl

Nolr: Fiml w n l was nol usrd for ~alalabnp ttie Coefiiaents to pred~cl the Chloride Profile

O 0 2 0 4 O 4 O 8 O IO O 12 0 14 O t6 O

Dapth [mm]

O O 2 O 4 0 60 8 O IO O 12 0 14 0 16 O

Depth [mm)

r comctmd comcbd c i CrConlintX ~ n d k b d 1 ~ a r u n m n t ~ . p t h D O D ~ -PMI Conc. IW concnta Cr Conbnt I 1 [I~JIOOOI 1111 J ~ O O O ~ [ ~ ~ J ~ o o o ] [ m i ] [ppml m r r ) n

452 37.5 39 8 1 .O 5928 5 0.5300 O 4580

Note; Fin1 point was no1 uaed la caladating the Cwnlamls lo pred~d Ihe Chlonde Praftle

b

Camcbd Comtbd Cr Cr ConbntX Pndkbd M o i i u m n t Wplh [hpth b p t h Conc. (%concnb Ci' Conbnt

[inllDoo] [lnllOOO] [lnlldoo] [mm] [PW) mir) X 452 37.5 40.5 1 .O 47lB 0.3883 O 3888 448 62.5 455 67.5 457 137.5

187.5 Average 237.5

453 287.5 337.5

Totilüepai 387.5 450 437.5

Nob. All points wers Malyred

O O 2 O 4 O eo a O 100 n a

Depth [mm]

0 O 1 O 4 0 6 0 4 O 10 0 1

Oepth (mm]

Simpk O l b of Grlndkip D i b of Anaiyrk KHz-1PW25-1 2-Jd-87 3-U-97

D@P* Comcbd Comcted CI' Cr Contant % Pndkbd Maasunmont Dopth OIpth l k p t h Conc. 4% concnb CI.Conan1

[ln J~OOO] [In JlOOO] 37.5 37.0

0 O 4 0 60 40 10 O 120

Dspth [mm]

Sampk Dib of Orindlng Dmm ot Anriyrb KH2-3P1-1 20-Jui-O7 26-J-97 1

WP* Comcbd Comcbd Cr CI' Conbnl W Prodkbd Mor8unmrnt b p l h b p t h lhpth Conc. (Xconcmb Cr Conbnt

IhJ1000) IInJlWO] [inJlOOO] Imm] tppm] m r r ) % 300 10 11.8 0.3 2382.5 0.1627 0.1847

Nota: All points wsra snalyxed

Dib of Orlndlng Rab of Aiulyrb KH2-3P4-1 3 4 - 9 7 4-Jd-97 I

mptfi Comcted Comcbd Cï CïConbntX Pmdkbd Mmisunnnnt Wpth a p t h Wpth Conc, (Xconcnm Cr Conenl

[hl t OW] [hJl0001 [lnJlOW] (mm] hpml mari) % 376 37.6 35.8 0.9 3838.6 0.3102 0.2561 373 62.5 80.8 1.5 2586 8 0.1852 O 1828 380 87.6 85.8 2.2 1922 7 0.11W O. 1228 384 130 128 3 3 3 1258.2 0.0521 0.0534

170 188.3 4.3 871.6 0.0237 0.0204 Avrnge 210 208.3 5.3 844.8 0.0110 O 0065 378.25 250 248.3 6.3 m 0,OOOû 0.0017

290 288.3 7 3 748.6 0.0012 00004 Toblhpth 330 328.3 8 3 758.8 O 0024 0.0001

380 370 368.3 O 4 752 6 0.0018 0.0000

Note: Fltsl pdnl wiis nol wed for falcu1iibng the Coerfiascilr !O ~ed ic t the Chlonds Profile

00 1 0 2 O 3 0 4 0 60 O0 1 0 8 0 9 0 100

Depth [mm]

n 0 s

q O,

O, e r 0 020 O L

O 016

E 3 o i o u '2: 0 O 0 5 E O

om O O 1 O 2 O r O 40 60 0 0 1 0 1 0 0 0 100

Ospth [mm]

Tohl h p t h 400

Comcwd Comcbd Cr Cr Conbn ln h p ü ~ h p t h Conc, (Xconcnb

(inlitlûô] (mm] [Ppml mu) 41.5 1.1 6270.4 0.5578

P n d k b d Ci' ConWnI

O 50111 O 3092 0 2899 0 1435 O 0607 O 0217 00068 0 O017 00004 00000

Note: Flrrt point was no1 ured loi ulalating the Coofiiaonls to prsdid Chlotide Prolle

Sampia Dlb of Orkidkrg Dib of Atuîyrh KH2-3P 18-1 2234-97 26-JIiI-97 1

1 h P k C o m c l d Comcbd Cr C l ~ o n b ~ % ~ P n d k b ~ ~ . a r u & m n t üopth üopm ûmpü~ Conr. ( ~ c 0 n c i . b Cr Conbnt

[icrliOOO] IkrllOOOl [ inl l Wô] [mm] bpml mu) % 51 1 37.5 47.3 1.2 8829.4 0.6234 O.MI6 508 82.5 607 87.5 512 137.6

187.6 Avenga 237.5 609.76 287.5

337.5 Tohl h p l h 387.5

500 487.5

Nob: Flnl point w r r not us& for caiadaünp h Cwffidenis to pr&a aM Chlonde Prdile

De pth [mm]

Atmendix C - Chloride Profiles C20

Cyclic Wetting and Drying and its Effects on Chlonde Ingres in Concrete

û a b of Orindlng Date of Anaiyak OVM WI 22-Fsb.97 23-Fsb-97

1

Corncbd Comcted CF CI' Conbnt % Pndlcbd

[ln Jl000] [in J10001 [in JI0001 [mm] mm) X 731 37.5 35.8 0.9 6430.1 0.5985 0.4184

I Nols: Flnt pdrit was ml ussd toc cdalat~ng tiw CoMiasnls lo prsba the Cîûonds P r â h

1 W P ~ Comcbd Cornctd Cr Ci' Conbnt X Pndkbd 1 Memursrnent OIpth h p a i lkpth Conc, (% concmta Cr Content

[in J I Ooo] IinJlOoo~ [inJloOO] [mm] h m 1 miss) X 1150 45 37.0 0.9 8050.3 0 7433 O 5807 1147 75 1158 1 O5 1153 175

245 Average 355

1152 465 615

Total h p t h 805 1160 1035

1145

l Nols: First point was ml used foc calwiating Vis Codfiasnlr to prodicl tho Chlonde Profils

O O 6 O 10 O 150 300

Depth [mm]

D i b of Grlndlng Da& of Anilysk 28-May -97 2Q-May-97 I Corncrd Corncrd Cr Cr Conbnt X Pndlcbd

M e a r u m n t Denth üanîh lknîh Conc. l%concmb cr Conbnl

. I Note: Flnl @nt war no1 wsd lof cdaliting the Coefilabnlr lo predict (he Chlmdo Prdils

1 mpm Comcbd C o m c l d CI' Cr Conbnl'K Prodkbd 1

572 37.5 584 62.5 584 87.5

145 Avenge 205

570.5 265 325

Totilûopth 385 580 44 5

505 565

Note: Flral point war no1 uied for calalotirtg me Coeîîiclmti 10 pfedict me Chlonde Profile

00 2 0 4 0 a0 a O 100 120

Depth [mm]

O O 2 O 40 8 O 1 O 100 12 O

Depth [mm]

&mpk Dib 01 Odnd h g Dlb of Anilyik KHz-6 W30-1 3-Jw-87 4-JUI-97 5-Ju~-97

f mpm Comcbd Cornctrd Cr Cr ConbntX Pndkbd 1

h m p b D a t of Grkidkig Dab ofAnrlpb KH2-BWB61 6 4 ~ 4 7 11 Jw-87

MP* ~ o m c t m i ~ o r n c b d Cr Cr ConbntX ~ n d k l * d Mmsunnnnt Dipth [kpm b p t h Conc. (Xconcnb Cr Conbnt

l lnllM)O] [ InJlOûû) [ i n l l û û û ] [mm] [ ~ p m l nuis.) % 876 37.5 38.5 1 .O 3840.1 0.2971 0.5335

Note: The first 4 panls m e no1 Miilped

Depth [mm]

D.P* C o m c b d ComcCd Cr CrConWntX PndkOId M o r 8 u m n t Ikplh Diplh OIpth Conc. ( % c o n c n a CI Conlsnt

~lnllOOO] [in.ilûOô] [inJloOa] {mm] [PPml mu) % 1088 37.5 37.0 O B 3018 8 0.2345 O 3737 1086 lOBl 1083

Avonpe 1088.5

T o b l DopW 1080

Noie:

O O 2 O 4 O 6 0 10 100 120 140 160 110 n I0

Depth [mm]

Sampk D i b of Orlndlng Dam of Analyak KH3-1P1-1 28-May-87 28-May-87 1

O I P ~ ~ o r n c l r d ~ o m c w d CF CT ~ontont x ~Gdktmd- Marsunment OIpth (kpth (kpth Conc. ( X concrab CI' Conbnt

[InJlOOO] [InJ1000] [inll OOO] [mm] [PP] mirs) X 206 10 12,s 0 3 2180.8 0.1428 O 2838 208 30 209 50 187 70

80 Avmngm 110

202.5 130 150

Totalilopth 170 200 190

Note: Flnl pan1 was no1 used for cslalaliw me Coo«iaenta Io predicl th8 Chlondo Profile

&mpk ü a b of Oilndlng Dab of A ~ l y a b KH3.1 P4-1 30.May.97 3-Jur-97 1

I MPW C o m c M Comcbd CI. Cr Contn tX Pndkbd 1

Avmngm 201.5

Conc.

4%- 3578.4 2246 1561.6 1181 3 939.7 842.8 789 1

(% concnte CI' Conbnt mci.8) X 0.3308 0.4287

Nota: Fkal poml wris no1 wed for caldrbng me Cooffidentr Io prsdid th8 C h l ~ d e Profile

S. = 1.626E41 m'la Cm= OAOU X = 0.BSU

O 0 0 1 10 3 1 2 O 2 6 3 O

Dspth [mm]

Sampk Dab of Grlndlng Dab of Analyrk KH3-1 PB-1 4-Jut-87 6-JUr-07 10-JmB7

1 h p t h Comciad Comciad Cr CrConiant% Prrdkted 1 Moarunmont Depth Dopth Depth Conc. (Xconcntr CI' Contrnt

lhJlOOO] [InAOOO] ~InJlOOO] [mm] [ppml mrr) X 421 10 12.5 0.3 5918.6 0 5274 0,5418

Nob: All points were Mdyzed

I w p m Comcbd C o r m r d Cr CI'ConlrnlW Pndkbd 1 Moaruremmnl Wpth Dopth (kpm Conc. (X concnb Cr Content

[hrlooo] [lnllooo] [lnlloool Imm] IPpml mr.) % 420 35 36.0 0.0 4883.7 0.4348 0 3738

Nole: Fin\ polnl war not used for cslalalng Ihe CMlaonts to predict tho Chloride Prdrle

00 2 0 4 0 1 0 8 0 10 0 I 2 0

Depth (mm]

00 2 0 4 0 8 0 8 0

Depth [mm]

&mpk Dai. of Orlndbg Da1 of Anilyak W3-1P25-1 17-Jm-97 18-Jw-97 1

B P * Comcmd Corncard Cr Cr Conbnl X Pndlclbd Meirunmrnl Mpth Oepth h p t h Conc. Wconcmte Cf Conbrn! 1 [inliûoo] [I~J~OOOI 0n~i0001 [mm] [ppm] m i r s ) x J

413 30 28.3 O 7 6486.8 0.5807 0.4981

Note: First paint was m t used for calailabnu the Codfidsnts Io predtd the Chlonds Prdtle

1 h p k Comcmd Corncbd Cr CTConbnlU P n d k W 1

Note: FIisI pomt wai not used for ccilcrrlaang the Costliuenls Io predict me Chdonde Profile

S. - 3.021E-12 m'la C o r 0.7221 I t= 0 . W

0 0 2 O 4 0 0 0 8 O 10 O 12 O

Depth [mm]

1 &mpb D i b of Grlndlno Dit. of Annly 8 ia 1 1 KH3-1PW4-1 26-Ju?-97 2.~d.97- 1

D.P& Comcbd Comcbd Cr CI' Conmnt % PndlcOId Merruromont DIpth üopth Deplh Conc. (%concnb CI' Contant

[inJlûOû] IinJlOôô] [inJlOW] [mm] fPPm1 m u r ) W 410 30 38.3 0.8 8080.4 0.5410 0.5350

Note: Al points wers Mdyzod

&l'th Comcbd Comcbd C t Cr Conant % Pndkml Mmsunnwnt üepm Wpth Ciopth Conc. ('ICconcreDI Cr Conmnt

[biJlOOO) IlnJ10001 [InJlOOO] [mm1 (ppm] mu) X 481 37.5 41.5 1 1 4274.8 0.3811 0.3337

Note: Flrd point wai not used (or uilalabng ttre Cdidenb 10 predict the Chlotida Proifla

O O 4 O 6 0 1 O 1 0 O 12 O

Depth [mm]

O O 2 O 4 O 8 O 10 10 0 12 O

Depth [mm)

1 SImpk D i b of Grlndlng Dab of Analysb 1

WP* Comcbd C0mct.d CI' Cf Conbnt W Pndlcbd Meisunment OIpth fhpth [kpm Conc. (% concnte CI' Canbnt

[inJi 0001 [in JlOOO] [ln Jt000) [mm] [ppm] marna) % 398 30 30.5 0.8 5102.6 0.44ôô 0.4379

Note: Al points waro Mirlymd

0 0 1 O 2 O 30 4 0 6 O 1 O 7 0 B O O0 10C

Dapth [mm]

1 -Pb û a t of Oilndlng D i b of Ar)ci)yik 1

I O . P ~ ~ o m c t d ~ornctmd Cr CtContnt% ~rodkted 1 Moi8uroment h p t h b p t h h p t h Conc. (X concnta CI'Conmnt

[in J l 0001 [ln Ji 0001 [Jnll Oôo] [mm] lppm] m s r ) X 203 10 12.3 0.3 1952.3 0.1198 0.1216

Nota; Al points were Mdyred

224 30 28.5 224 50 48.5 222 70 88.5

BO 88.5 Avrngr 112.5 111.0

223.5 137.5 1380 162.5 161.0

Totrl b p t h 167.6 1860 225 212.5 211 O

Note: NI points were anaiyzed

00 10 2 0 5 O 4 O 6 0 I

Depth [mm]

t D.P* ~omctid Cornerd Cr CrContantX P n d k r d 1 Mei iunmnt lkplh h p t h Wpth Conc. (% concnar CTConbnt

(InJI 000) [ln 110001 (ln11 0001 [mm] [p pm] miai ) % 339 30 28.5 0.7 5346.7 0.4603 0.3989 338 50 338 70 330 90

130 Average 170

338.5 210 2 9

TohlDepth 280 340 330

Noto: FLnt point war no\ w d foc cdcrlabng the Coefiidms Io predict the Chlonde Prolile

1 MPm Comcbd Comcbd Cr Cr Conbnt% Pndkbd 1 [Pm1 mu) % I

410 30 32.3 0.0 7054.6 0.0364 O 5644 405 M) 52.3 388 70 72.3 395 110 112.3

150 152.3 Avrnge 180 102.3 402.25 230 232.3

270 272 3 Total h p î h 310 312.3

400 3ûû 392.3

Nols: Firsl poinl was no! u s 4 for calcriabng the Coefficients to predid the Chlonde Profils

S. rn 7.622E.12 m'le Ce= 0.6036 % * 03976

O 0 $ 0 2 0 3 O 4 O 50 4 0 70 6 0 90 W C

Depth [mm]

0 0 1 O 2 O 30 4 0 5 O 6 0 7 0 8 0 90 IOC

Depth [mm]

&mpk D i b of Otkidlnu (kir of Anilyub KH3-3P2S-1 23-JJ-87 26Jd-97 1

b P m Corrrcbd Corncbd Cr CI' Content % Pndkbd Moi iunmnt Dopth h p t h ihp* Conc. (Xconcnto C1'Conimnt

(inl1OOâl [inJlOOOl (lnJ1000~ (mm1 [ppm] mu) TL 500 37.5 40.0 1.0 7654.5 0.7074 0.6975

Note; All punk were Mdyzed

Comcîod Comctod CI' Cr ConbntX ~ n d k m i Mmrunmrnl ôopth Dmpth Depth Conc. ( X concnb Cl' Conbnt

[InJlOQO] [h l1 0001 [lnll OOO] [mm] Ippm] nusr) W 74 1 37.5 43.0 1.1 4851.1 0.4172 0.3470 73 1 112.5 118.0 717 187.5 193.0 733 282.5 288.0

337.5 343.0 Avrngm 412.5 418.0

730.5 487.5 4930 5625 5880

Total b p t h 637.5 6430 725 712.5 718.0

-Ph ûab 01 Orlndlng Dab of Analyrb KH3-8385-1 1 8-D0~-97 21-DM-97 22*D%.B7

M#a@unmrnt k p t h üepth (kpth Conc. (Xconcnb Cr Conwnl lhJlOOO] [InJlOOO] [lnJlOOO) [mm) IPpml mais) X

1042 35 40.5 1.0 6701.7 0.5145 0.4480

Nota: fha iad 2 pdntr wsra Ignorai, nnd the first point was not used for cdalabng the Codiaenls t o Predë the Chloride Profile

O O 5 O IO O 15 O 100 ma

Depth [mm]

1 Sampk D i b of Orindlng [ k W of Analyak 1

1 a P m Comcbd Comcbd CT CI. ~onmnt x Pndkbd 1 I kaaunmrnt ~ ~ ( t i W D ~ ~ . ~ ( t i Conc. I X concnb ~ ~ . c o n m n t I

Dalr of Orindlng Dalr o f h i y a k KH3-38120-1 W ~ r . 9 7 1 1 -J~+97 I

1 h p m Comclrd C o m c W Cr CTConbntX Pndkbd 1

f obl lkpm 750

Conc.

JE!L 4574 1 3848.8 3û27.7 1825.1 1099.8 818.2 760 3 699

661.5 882.8

lLPbr

(% concnb m r a ) 0.3817 O. 2892 0.2370 0.1168 OB443 0.0161 0.0103 0.0042 0.0004 0.0028 00000

Cr Conbnt

0.3501 0.2997 0.2455 0.1178 O 0452 0.0138 0.0033 00006 0.0001 0.0000 00000

Nolo: Flrrt polnt wss no1 wod fa ccilalsbng Iho Cwfiidenls lo predict (ho Chl~nde ProMo

O0 2 O 4 0 6 O 8 O 100 12 O 14 0 10 O

Deplh [mm)

- --

h P h Comcbd C o m c l d Cr CïConbnlX Pndkbd Maaaunmont lkpth lkpth (kpth Cont. (X concnb Cr Content

[ I n J l O ~ [InlWûû] pnJ1000) [mm] lppml m a i ) X 780 45 48.5 1.3 5885.6 0.2877 O 2931

--

b P * C o m M Comebd C i CiConllnt% ~~ndkbd ~ i a u ~ n t b p t h lkpth Dopth C0nt. (Xconcnb CTConant

[InIlOôô] [InllOôôl [inllOOO] [mm] I p P d m m ) X L

724 45 48.8 1.3 30486 0.2408 0.3004

D, 8.18OE-13 m'la C,' 0.3781 % 8 O.Un16

1 W P ~ Comcmd Comcwd Cr C i Conwnt% Pndkbd 1 M e a i u m n t Depth Dapth h p t h Conc. (Xconcnb Cî' Conoint [inlIOWl] [inllOOo) fînJlOOOl [mm] Ippm] mari) %

720 45 44.8 1 2âO1.3 0.2248 0.2865

Sample KHI-SI4 Diameters 99.32 99.36 Date 15-Aug-96 Average Diameter 99.34 Time Q:45am Area 7751 mm2

Mistake was made during first run and the sample was allowed to redry

R Square 0.8621 lntercept 0.0189 Sorptivity 0.0041

Time [min]

O 1 2 3 4 6 9 12 16 20 25

Sample Date Time

Time

[min1 O 1 3 4 6 9 12 16 20 25

Mass

[gl 91 8.49 91 8.66 91 8.66 918.69 918.71 918,72 918.75 918.78 918.77 918.76 918.78

Change in

Mass [gl 0.00 0.17 0.17 0.20 0.22 0.23 0.26 0.29 0.28 0.27 0.29

Rate of Square Root Absorption

[mm1 0.000 0.022 0.022 0.026 0.028 0.030 0.034 0.037 0.036 0.035 0.037

KHI-SI-2 Diameters 14-Aug-96 Average Diameter 9:30am Area

Mass

[SI 918.80 91 9.07 919.05 91 8.99 918.98 919.01 91 9.00 91 9.02 91 9.02 919.02

Rate of Change in Absorption

Mass I91 [mm1 O. 00 o. O00 0.27 0.035 0.25 0.032 O. 19 0.025 O, 18 0.023 0.2 1 0.027 0.20 0.026 0.22 0.028 0.22 0.028 0.22 0.028

of Tirne [minlR] 0.000 1 .O00 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

99.35 99.47 777 1

Square Root of Time [minlR] 0,000 1 .O00 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

Regressed Data Points

[mm1 0.01 9 0.023 0.025 0.026 0.027 O. 029 0.031 0.033 0.035 O. 037 0.039

99.59

mm2


[mm1 0.031 0.030 0.029 0.029 0.029 0.028 0.028 0.027 O. 02 7 0.026

KH1S1-1 Sorptivity

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of Tlme [minAO.o]

R Square 0.0994 lntercept 0.0306 Sorptivity -0.0008

0.0 1 .O 2 .O 3.0 4.0 5.0 Square Root of Tlme [mlnA0.6)

Sample Date Time

Time [min]

O 1 2 3 4 6 9 12 16 20 25

Sample Date Time

Time [min]

O 1 2 3 4 6 9 12 16 20 25

KHI-SI-3 Diameters 99.58 99.64 14-Aug-96 Average Diameter 99.61 10:OOam Area 7793 mm2

R Square 0.9781 lntercept 0.0202 Total Average 0.0195 Sorptivity 0.0065 Total Average 0.0053

Mass

[SI 927.47 927.66 927.70 927.72 927.74 927.77 927.77 927.81 927.83 927.85 927.88


Mass [9l [mm1 0.00 0,000 0.19 0.024 0.23 0.030 0.25 0.032 0.27 0.035 0.30 0.038 0.30 0.038 0.34 0.044 O. 36 0.046 0.38 0.049 0.4 1 0.053

Square Root of Time [minlR] 0.000 1 .O00 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

KH 1 -S3-1 Diameters 99.6 16-Aug-96 Average Diameter 99.5 9:20am Area

Mass

191 903.49 903.76 903.77 903.79 903.83 903.84 903.87 903.90 903.94 903.99 904.02

Change in

Mass bl 0.00 0.27 0.28 0.30 0.34 O, 35 0.38 0.41 0.45 0.50 0.53

Rate of Absorption

[mm1 0.000 0.035 0.036 0.039 0.044 0.045 0.049 0.053 0.058 0.064 0.068

7776

Square Root of Time [minlR] 0.000 1 .O00 1 .Al4 1.732 2.000 2.449 3.000 3.464 4.000 4,472 5.000


[mm1 0.020 0.027 0.029 0.032 0.033 0.036 0.040 0.043 0.046 0.049 0.053

99.4

mm2


h m 1 0.025 0.033 0.037 0.039 0.042 0.046 0.050 0.054 0.059 0.063 0.067

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of Tlme [mlnA0.6]

R Square 0.9871 lntercept 0.0247 Sorptivity 0,0085

0.0 1 .O 2.0 3.0 4,O 5.0 Square Root of Tlme [mlnA0,6]

Sample Date Time

Time

(min1 O 1 2 3 4 6 9 12 16 20 25

Sample Date Time

Time [min]

O 1 2 3 4 6 9 12 16 20 25

KH 1 -S3-2 Diameters 99.1 16-Aug-96 Average Diameter 99.1 9:20am Area 771 3

Mass

kl1 924.64 924.80 924.85 924.88 924.89 924.93 924.95 924.99 925.01 925.07 925.09


Mass [gl Imml 0.00 0.000 0.16 0.021 0.21 0,027 0.24 0.031 0.25 0.032 0.29 0.038 0.31 0.040 0.35 0.045 0.37 0.048 0.43 0.056 0.45 0.058

Square Root of Time [min1'] 0.000 1 .O00 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

KH 1433-3 Diameters 99.6 16-Auge96 Average Diameter 99.65 9:50am

Mass

[SI 916.71 916.86 916.89 916.92 91 6.95 916.96 91 7.00 91 7.04 91 7.06 917.07 917.11

Change in

Mass [gl 0.00 O. 15 0.18 0.2 1 0.24 0.25 0.29 0.33 0.35 0.36 0.40

Ar ea

Rate of Absorption

[mm1 0.000 0.01 9 0.023 0.027 0.031 0.032 0.037 0.042 0.045 0.046 0.05 1

7799

Square Root of Time [min''] 0.000 1 .O00 1 A l 4 1.732 2.000 2.449 3.000 3.464 4 .O00 4.472 5.000

99.1

mm2


[mm1 0.01 4 O. O23 0.027 O. 030 0.032 0.036 0.041 0.045 0.050 O. O54 0.059

99.7

mmz


mm1 0.01 3 0.021 0.024 0.027 0.029 0.032 0.037 0.040 O .O44 0.048 0.052

R Square 0.9869 lntercept 0.0141 Sorptivity 0,0090

0.0 1 .O 2.0 3.0 4.0 6.0 Square Root of T lme (mln60.6)

R Square 0.9826 lntercept 0.01 31 Total Average 0.01 73 Sorptivity 0.0078 Total Average 0.0084

-

KH143-3 Sorptivity 0.070

0.060 I

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of Tlme [mlnAO.o)

Sample Date Time

Time [min]

O 1 2 3 4 6 9 12 16 20 25

Sample Date Time

Time [min1

O 1 2 3 4 6 9 12 16 20 25

KH2-SI-1 Diameters 99.7 21 -Aug-96 Average Diameter 99.7 9:30 AM Area 7807

Mass

191 934.04 934.20 934.19 934.20 934.22 834.24 934.26 934.25 934.27 934.29 934.29


nhss [gl mm1 0.00 0,000 0.16 0.020 0.15 0.019 0.16 0.020 O. 18 0.023 0.20 0.026 0.22 0.028 0.2 1 0.027 0.23 0.029 0.25 0.032 0.25 0.032

Square Root of Time [minlR] 0.000 1,000 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

KH2-Si-2 Diameters 99.7 21 -Aug-96 Average Diameter 99.65 9:30 AM Area

Mass hl

930.37 930.57 930.56 930.57 930.58 930.58 930.59 930.60 930.60 930.61 930.62


Mass [gl [mm1 0.00 0.000 0.20 0.026 0.19 O. 024 0.20 0.026 0.21 0.027 0.21 0.027 0.22 0.028 0.23 0.029 0.23 0.029 0.24 0.031 0,25 0.032

7799

Square Root of Time [min1'] 0.000 1 .O00 1.414 1,732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

99.7

mm2


Imml 0.016 0.019 0.021 0.022 0.023 0.024 0.026 0.028 0.030 0.031 0.033

99.6

mmz


(mm1 0.023 0.025 0.025 0.026 O. O26 0.027 0.028 0.029 0.030 0.031 O. O32

R Square 0.9330 lntercept 0,0161 Sorptivity 0.0034

KHZSI -1 Sorptivity 0.045

0.040

0.0 1 .O 2. O 3.0 4.0 5.0 Square Root of Tlme [mlnAO.S]

R Square 0.9454 lntercept 0.0229 Sorptivity 0.001 8

KH241-2 Sorptivity

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of T h e [mlnAO.o)

Sample KH2-SI -3 Diameters Date 21 -Aug-96 Average Diameter Time

Time [min]

O 1 2 3 4 6 9 12 16 20 25

Mass

[SI 927.35 927.49 927.48 927.48 927.51 927.52 927.52 927.52 927.53 927.54 927.55

Sample KH2-S3- Date Time

Time

b j n l O 1 2 3 4 6 9 12 16 20 25

Area


1 Diameters 23-Aug-96 Average Diameter

Mass

[gl 91 5.83 916.03 Q16,05 916.06 916.06 916,08 916.08 916.10 916,lO 916.12 916.13

Change in

Mass tg1 0.00 0.20 0.22 0.23 0.23 0.25 0.25 0.27 0.27 0.29 0.30

Area

Rate of Absorption

[mm1 0.000 0.026 0.028 0.029 0.029 0.032 0.032 0.035 0.035 0.037 0.038

Square Root of Time [min''] o. O00 1,000 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000


[mm1 0.01 5 0.01 7 0.018 0.01 9 0.01 9 0.020 0.021 0.022 0.023 0.024 0.026

Square Root of Time [min14 0.000 1 .O00 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5,000


[mm1 0.024 0.027 0.028 0.029 0.030 0.031 0.033 0.034 0,036 0.037 0.039

R Square 0.8684 lntercept 0.0149 Total Averagl 0.01 80 Sorptivity 0.002 1 Total Averagi 0.0024

l 0.0 1 .O 2.0 3.0 4.0 I I Square Root of Tlme [mlnn0.6] =,O 1

I


KH243-1 Sorptivity

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of Tlme (rnlnnO.o]

Appendix D - Sorptivity Data D6

~ = o * Q ) ~ C V ~ * o o ~ o ~ 2 3 0 - TqNqqq.c?o Cu m o o o o o o o o o o o 6 =


Sample Date Time

Time [min1

O 1 2 3 4 6 9 12 16 20 25

Sample Date Time

Time [min]

O 1 2 3 4 6 9 12 16 20 25

KH3-Si-1 Diameters 99.9 99.6 28-Aug-96 Average Diameter 99.75 10:OO AM Area 7815 mm2


Mass

[gl 970.09 970.23 970.27 970.26 970.25 970.27 970.30 070.29 970.27 970.30 970.31


Mass [gl Cmml 0.00 0.000 0.14 0.01 8 0.18 0.023 0.17 0.022 0.16 0.020 O. 18 0.023 0.21 0.027 0.20 0.026 0.18 0.023 0.21 0.027 0.22 0.028

Square Root of Time [min''] 0.000 1 .O00 1 .Al4 1.732 2.000 2.449 3.000 3.464 4.000 4,472 5.000


[mm1 0.01 8 0.020 o. 02 1 0.021 0.022 O. O23 O. O24 0.025 0.026 0.027 O. O28

KH3-S 1-2 Diameters 99.6 99.8 28-Aug-96 Average Diameter 99.7 10:30 AM Area

Mass [SI

982.57 982.78 982.79 982.78 982.78 982,78 982.82 982.82 982.84 982 -84 982.86


Mass hl (mm1 0.00 0.000 0.21 0.027 0.22 0.028 0.21 0,027 0.21 0.027 0.21 0.027 0.25 0.032 0.25 0.032 0.27 0.035 0.27 0.035 0.29 0.037

Square Root of Time [min"] 0.000 1.000 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000


[mm1 0.023 O. O26 0.027 0.028 0.028 0.030 0.031 0.032 0.034 0.035 0.036

0.0 1 .O Square 2.0 Root ot Tlme [rnlnAO,o] 3.0 4.0 5.0


KH3S1-2 Sorptivity

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of Tlme (mlnh0.q

Sample KH3-SI -3 Diameters 99.6 99.6 Date 28-Aug-96 Average Diameter 99.6 Time 10:30 AM Area 7791 mm2

Rate of Square Root Regressed Time Mass Change in Absorption of Time Data Points

Sample KH3-S3-1

[min'] 0.000 1,000 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.485 5.000

Diameters 99.8 Date 30-Aug-96 Average Diameter 99.7 Time 9:45 AM Area 7807 mm2

Rate of Square Root Regressed Ti me Mass Change in Absorption of Time Data Points [min]

O 1 2 3 4 6 9 12 16 20 25

[min''] 0.000 1 .O00 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

R Square 0.9314 lntercept 0.0192 Total Averag 0,0200 Sorptivity 0.0026 Total Averag 0.0024

O. 0 1 .O 2.0 3.0 4.0 6.0 Square Root of Tlme [rnln60.6)

R Square 0.8527 lntercept 0.0294 Sorptivity 0.001 7

O. 0 1 .O 2.0 3.0 4.0 5.0 Square Root of Time [mlnA0.6]

Sample Date Time

Time

[min1 O 1 2 3 4 6 9 12 17 20 25

Sample Date Tirne

Time [min]

O 1 2 3 4 6 9 12 16 20 25

KH3-S3-2 Diameters 99.8 30-Aug-96 Average Diameter 99.85 i0:15 AM Area 7830

Mass

[gl 982.12 982.34 982.32 982.31 982.33 982.34 982.36 982.38 982.40 982.40 982.41

Change in

Mass [gl 0.00 0.22 0.20 0.19 0.21 0.22 0.24 0.26 0.28 0.28 0.29

Rate of Absorption

(mm1 0.000 0.028 0.026 0.024 0.027 0.028 0,031 0.033 0.036 0.036 0.037

Square Root of Tirne [min1'] 0.000 1 .O00 1.414 1,732 2.000 2.449 3.000 3.464 4.123 4.472 5.000

Mass Ch

Diameters 99.9 Average Diameter 99.75

Area

Rate of ange in Absorption

781 5

Square Root of Time [minlR] 0.000 1 .O00 1.414 1.732 2.000 2.449 3.000 3.464 4.000 4.472 5.000

99.9

mm2


[mm1 0.021 0,025 0.026 0.027 0.028 0,029 0.031 0.032 0.035 0.036 0.037

99.6

mm2


Imml 0,020 0.022 0.023 0.023 0.024 0.025 O. O26 0.027 O. O28 0.029 0.030


KH3S3-2 Sorptivity

0.0 1 .O 2,O 3.0 4.0 5.0 Square Root of Tlme [mlnA0.6)

R Square 0.8296 lntercept 0.0200 Total Averag 0.0236 Sorptivity 0.0020 Total Averag 0.0023

KH3S3-3 Sorptivity

0.0 1 .O 2.0 3.0 4.0 5.0 Square Root of Tlme [mlnA0.6J

IMAGE EVALUATION TEST TARGET (QA-3)

APPLIED IMAGE. lnc - = 1653 East Main Street - -. - - Rochester. NY 14609 USA -- -- - - Phone: 71 6/482-OXlO -- -- - - Fax: 71 6/28û-5989

Cyclic Wetting and Drying and Chloride · between saturated and partially saninited States, as they...

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