Advantages of the Penetron® Integral

Waterproofing System with a focus on Penetron® Admix

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Contents

1. Introduction .................................................................................................................... 4 2. Problems associated with concrete waterproofing .......................................................... 4

2.1. Corrosion ................................................................................................................ 5 2.2. Carbonation ............................................................................................................ 6 2.3. Cracking ................................................................................................................. 6

2.3.1. Plastic shrinkage cracking................................................................................ 6 2.3.2. Drying shrinkage .............................................................................................. 7 2.3.3. Thermal cracks ................................................................................................ 7 2.3.4. D-Cracking ....................................................................................................... 7

2.4. Alkali Silica Reaction (ASR) .................................................................................... 8 2.5. Damage due to freeze-thaw cycles ......................................................................... 9 2.6. Concrete deterioration due to chemical attack ...................................................... 10 2.7. Sulfate attack ........................................................................................................ 11 2.8. Concrete structures in marine environments ......................................................... 11

3. Waterproofing with Penetron Admix ............................................................................. 12 3.1. How it works ......................................................................................................... 12 3.2. Features and benefits of Penetron Admix ............................................................. 13

3.2.1. Permanent concrete protection ...................................................................... 13 3.2.2. Self-healing concrete ..................................................................................... 14 3.2.3. Corrosion protection of reinforcement steel with Penetron Admix .................. 16 3.2.4. Protection against chloride penetration .......................................................... 17 3.2.5. Protection against carbonation ....................................................................... 19 3.2.6. Crack bridging ability of Penetron .................................................................. 19 3.2.7. Increase in compressive strength ................................................................... 22 3.2.8. Resistance against high water pressure ......................................................... 22 3.2.9. Chemical resistance ....................................................................................... 25 3.2.10. Resistance to freeze-thaw cycles ................................................................... 28 3.2.11. Compatibility with commonly-used concrete mix designs (Penetron Admix) .. 28 3.2.12. Prevention of Alkali-Silica-Reaction (ASR) ..................................................... 29 3.2.13. Limitations ..................................................................................................... 29 3.2.13.1. Cold joints .................................................................................................. 29 3.2.13.2. Active leaks ................................................................................................ 30 3.2.13.3. Concrete defects ........................................................................................ 30

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3.2.13.4. Structural cracks ........................................................................................ 30 3.2.13.5. Exposed concrete structures (thermal cracks) ............................................ 30

4. At one glance - Benefit overview .................................................................................. 31 5. Comparison of Penetron products with other waterproofing systems ........................... 32

5.1. Comparison between Penetron and hydrophobic pore blockers............................ 34 6. Application instructions – Penetron Admix ................................................................... 35

6.1. Description ............................................................................................................ 35 6.2. Dosage Rate ......................................................................................................... 36 6.3. Mixing ................................................................................................................... 36

6.3.1. Ready Mix Plant – Dry Batch Operation ......................................................... 36 6.3.2. Ready Mix Plant - Central Mix Operation ....................................................... 36 6.3.3. Precast Batch Plant ....................................................................................... 36 6.3.4. Technical Services ......................................................................................... 36

6.4. Setting time and strength ...................................................................................... 37 6.5. Limitations ......................................................................................................... 37

7. Application instructions – Penetron .............................................................................. 37 7.1. Description ............................................................................................................ 37 7.2. Consumption ......................................................................................................... 37

7.2.1. Construction slabs ......................................................................................... 37 7.2.2. Construction joints ......................................................................................... 38 7.2.3. Blinding concrete ........................................................................................... 38

7.3. Surface Preparation .............................................................................................. 38 7.4. Mixing ................................................................................................................... 38 7.5. Application ............................................................................................................ 38

7.5.1. Slurry consistency .......................................................................................... 38 7.5.2. Dry powder consistency (for horizontal surface only) ..................................... 38 7.6. Post treatment ................................................................................................... 38

8. Application instructions – Penetron Plus ...................................................................... 39 8.1. Description ............................................................................................................ 39 8.2. Coverage .............................................................................................................. 39 8.3. Application Procedures ......................................................................................... 39 8.4. Curing ................................................................................................................... 40 8.5. Technical Services ................................................................................................ 40

9. Contact and Disclaimer ................................................................................................ 40

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Table of Figures

Figure 1 Corrosion stages ..................................................................................................... 5 Figure 2 Example of plastic shrinkage cracks ....................................................................... 8 Figure 3 Example of drying shrinkage cracks ........................................................................ 8 Figure 4 Example of thermal cracking ................................................................................... 8 Figure 5 Example of D-cracking ............................................................................................ 8 Figure 6 Scanning electron microscope image of chert aggregate particle with numerous internal cracks due to ASR; cracks extend into the adjacent cement paste ........................... 9 Figure 7 Detail of aggregate showing alkali-silica gel extruded into cracks within the concrete. Ettringite is also present within some cracks ......................................................................... 9 Figure 8 Examples of ASR damage ...................................................................................... 9 Figure 9 Example of freeze-thaw damage on roads and bridge decks ................................ 10 Figure 10 Example of concrete damage caused by chemical attack ................................... 11 Figure 11 How Penetron works ........................................................................................... 13 Figure 12 Scanning Electron Microscope Photograph of Penetron crystals ......................... 13 Figure 13 Test setup, MFPA Leipzig, Germany, 2006 ......................................................... 14 Figure 14 Water flow through 0.2mm crack at water pressures of 0.1, 0.5 and 1.0 bar ....... 15 Figure 15 Water flow through 0.25mm crack at water pressures of 0.1, 0.5 and 1.0 bar ..... 15 Figure 16 Excerpt: Permeability of Penetron-Admix-treated concrete vs. control sample (ENCO, 2006) ..................................................................................................................... 17 Figure 17 Excerpt: Chloride permeability of Penetron Admix (AASHTO-T-277: Shimel and Sor, USA, 2005) .................................................................................................................. 18 Figure 18 Excerpt: Results of the rapid chloride penetration test at Sardar Patel, India, 2009 ........................................................................................................................................... 18 Figure 19 Seawall treated with Penetron Admix, Portocel, Aracruz, Brazil .......................... 19 Figure 20 The Capri, Miami Bay, USA. Basement structure treated with Penetron Admix ... 19 Figure 21 Backscattered Electron Image (BEI) of Penetron crystals forming in a crack. ...... 20 Figure 22 Needle-like, elongated Penetron forming in the cracks ........................................ 20 Figure 23 Excerpt: Permeability results of cracked concrete samples treated with Penetron ........................................................................................................................................... 21 Figure 34 OFI sample set-up (Penetron ―sandwich-system‖) ............................................... 21 Figure 24 Excerpt: Test results for Penetron Admix under 20 bar head water pressure, University of Bologna, Italy, 2005 ........................................................................................ 25 Figure 25 University of Bologna: Chemical resistance test - Test set up ............................. 26 Figure 26 University of Bologna: Chemical resistance test - results .................................... 27 Figure 27 Milan South Waste Water Treatment Plant, Italy ................................................. 28 Figure 28 SABESP Sewage Treatment Plant, Brazil ........................................................... 28

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1. Introduction

Penetron integral concrete capillary waterproofing systems are being used for more than three decades to effectively waterproof and protect concrete structures around the world. This document explains the most common problems associated with concrete structure in contact with water and under different environmental conditions.

The text further elaborates on how to address and prevent these problems with the help of Penetron® integral concrete capillary waterproofing systems in order to enhance the durability of concrete and effectively protect structures.

2. Problems associated with concrete waterproofing

Concrete is the most commonly-used man made construction material in the world. It possesses a relatively good resistance to water and structural concrete elements can be shaped rather easily into various shapes and sizes. Despite its durability, concrete – even high-quality concretes – is a porous material. Evaporating excess water in the hydration stage of the concrete will leave millions of pores and capillaries in concrete. Further the interfacial transmission zones (IZT) – a part of the concrete microstructure that describes the zone, which exists between the hydrated cement paste and large particles of aggregate – are prone to cracking during the hardening stage of the concrete due to shrinkage, temperature stresses and externally applied loads. These microcracks in the interfacial transition zone are usually larger than most capillary cavities present in the concrete. The pores and microcracks (especially if interconnected throughout the concrete) increase the porosity of the concrete matrix and will allow air and water to enter the hardened concrete. This will result in corrosion of the embedded reinforcement steel and in other concrete damages caused by water-borne salts and chemicals and further contribute to the deterioration and weakening the strength of the concrete, directly affecting its durability.

Water (seawater, groundwater, river water, lake water, snow, ice and vapor) is a primary agent for both creation and destruction of concrete – and is deeply involved in nearly every form of concrete deterioration. Field experience shows that, in order of decreasing importance, the principal causes for deterioration are the corrosion of reinforced steel, exposure to cycles of freezing and thawing, alkali-silica reaction, and chemical attack.

With each of these four causes of concrete deterioration, the permeability and presence of water are implicated in the mechanisms of expansion and cracking.

The problem of porosity and cracking of concrete is increased in structures that are constantly exposed to different loads, stress redistribution and tectonic seismic influences.

The following chapter focuses on the major deterioration causes of concrete:

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2.1. Corrosion

The corrosion of the steel reinforcement is the most common source of distress in concrete, especially concrete that is located near or under water. Corrosion of steel is an electrochemical process and basically is the transformation of metallic iron to rust, which is accompanied by an increase in volume (which in some cases – depending on the state of oxidation - can be as much as 600 percent of the original steel). This expansion of the rebar is then leading to concrete expansion and cracking, followed by spalling and eventually to a complete loss of the concrete cover. The final result will be the weakening of the structures’ strength and ultimately its failure.

Corrosion can occur when two dissimilar metals are embedded into concrete (such as e.g. steel and aluminum), because each metal has a unique electrochemical potential. The concrete then effectively becomes a battery. When the metals are in contact in an electrolyte, the less active metal corrodes.

If only one type of steel is present in the concrete, corrosion is generated by differences in the concentration of dissolved ions, such as alkalies and chlorides. These ions are introduced to the concrete by water penetrating into the pores and microcracks.

Figure 1 Corrosion stages

Hydrated Portland cement contains alkalies in the pore fluid and a sufficient amount of solid calcium hydroxide in order to maintain an alkalinity level with a pH value above 12. In an alkaline environment (pH value above 11.5) normal steel and iron form a thin, impermeable and strongly adherent iron-oxide film that makes the metals passive to corrosion. However, once the alkalies and most of the calcium hydroxide have either carbonated or leached away, the pH of the concrete surrounding the reinforcement may drop below 11.5 destroying the passivity of steel and allowing the corrosion process to start. In the presence of chloride ions the passivating film is destroyed even at pH values of above 11.5. The main causes of chloride in concrete are admixtures, salt-contaminated aggregate and penetration of deicing salt solutions and seawater.

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2.2. Carbonation

Carbonation occurs when carbon dioxide from the air penetrates the concrete and reacts with hydroxides, such as calcium hydroxide, to form carbonates. In the reaction with calcium hydroxide, calcium carbonate is formed.

This reaction reduces the pH of the pore solution to as low as 8.5, at which level the passive iron-oxide film of the steel is not stable and corrosion will set in.

Carbonation is highly dependent on the relative humidity of the concrete. The highest rates of carbonation occur when the relative humidity is maintained between 50% and 75%. Below 25% relative humidity, the degree of carbonation that takes place is considered insignificant. Above 75% relative humidity, moisture in the pores restricts CO2 penetration. Carbonation-induced corrosion often occurs on areas of building facades that are exposed to rainfall, shaded from sunlight, and have low concrete cover over the reinforcing steel.

Carbonation of concrete also lowers the amount of chloride ions needed to promote corrosion. In new concrete with a pH of 12 to 13, about 7,000 to 8,000 ppm of chlorides are required to start corrosion of embedded steel. If, however, the pH is lowered to a range of 10 to 11, the chloride threshold for corrosion is significantly lower—at or below 100 ppm. Like chloride ions, however, carbonation destroys the passive film of the reinforcement, but does not influence the rate of corrosion.

2.3. Cracking

Cracks generally increase the porosity of concrete and allow water and water-borne salts and chemicals to enter the concrete and accelerate its deterioration. Cracking of concrete can have a number of causes. In this document we only want to focus on the most common types of cracks in concrete structures.

2.3.1. Plastic shrinkage cracking

Plastic shrinkage cracks occur due to a rapid loss of water from the surface of concrete before it has set. This happens when the rate of evaporation of surface moisture of freshly placed concrete exceeds the rate at which bleed water can replace it. Tensile stresses develop in the weak, hardening plastic concrete as a result of the restraint provided by the concrete below the drying surface layer. Plastic shrinkage cracks are usually shallow in nature and do not intersect the perimeter of the slab. However, like every crack they provide a possible entry-point for water and chemicals into the concrete structure and as such a starting point of the deterioration process.

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2.3.2. Drying shrinkage

As almost every concrete mix design contains more water than is needed to hydrate the cement, much of the remaining water evaporates, causing the concrete to shrink. Restraint to shrinkage, provided by the subgrade, reinforcement or another part of the structure, causes tensile stresses to develop in the hardened concrete. Restraint to drying shrinkage is the most common cause of concrete cracking.

2.3.3. Thermal cracks

Thermal cracking takes place if an excessive temperature difference exists within a concrete structure or its surroundings. This difference in temperature causes a higher contraction of the cooler portion over the warmer part of the concrete. This restrains the contraction. If the restraint causes tensile stresses that exceed the placed concrete’s tensile strength, thermal cracks will occur. In some climate zones thermal cracks can occur as a result of the atmospheric temperature differences. During daytime high temperatures cause the concrete to heat up and expand. At night the air temperature falls significantly and leading to a contraction of the concrete mass. This can cause concrete to crack. Due to the expansion and contraction of the concrete in air temperature differences these cracks widen further over time.

2.3.4. D-Cracking

D-cracking is a form of freeze-thaw-cycle deterioration and often observed in concrete pavements (usually taking place along the joints). Water accumulation in the base of the concrete ultimately saturates the aggregate. Once free-thaw cycles set in the aggregate begins to crack and subsequently crack open the concrete. This process usually starts at the bottom of the slab and progresses upwards to the surface.

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Figure 2 Example of plastic shrinkage cracks

Figure 3 Example of drying shrinkage cracks

Figure 4 Example of thermal cracking

Figure 5 Example of D-cracking

2.4. Alkali Silica Reaction (ASR)

Alkali-silica reaction (ASR) is the most common form of alkali-aggregate reaction (AAR) – together with the much less common form alkali-carbonate-reaction ACR – and can cause serious expansion and cracking in concrete, resulting in major structural problems and sometimes necessary demolition. ASR is caused by a reaction of between the hydroxyl ions in the alkaline cement pore solution in the concrete and reactive forms of silica in the aggregate (e.g. chert, quartzite, opal, strained quartz crystals). A gel is produced, that increases in volume by taking up water and so exerts an expansive pressure, resulting in the failure of concrete. This gel can occur in cracks and even within the aggregate particles.

In order for ASR to occur in concrete a sufficiently high alkali content of the cement (or alkali from other sources), a reactive aggregate (e.g. chert or quartzite) and finally water is needed

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for the reaction. If no water is present in the concrete, no ASR will take place as the alkali-silica gel formation requires water.

The best way to avoid ASR is to use non-reactive aggregates, which are not always available. In this case it is essential for the concrete mix designer to be aware of the Na2O-equivalent (in %) of all products used in the concrete mix. This is to ensure that the Na2O equivalent value does not exceed the acceptable amount per m3 (usually set around 3.5kg/m3).

Figure 6 Scanning electron microscope image of chert aggregate particle with numerous internal cracks due to ASR; cracks extend into the adjacent cement paste

Figure 7 Detail of aggregate showing alkali-silica gel extruded into cracks within the concrete. Ettringite is also present within some cracks

Figure 8 Examples of ASR damage

2.5. Damage due to freeze-thaw cycles

In cold climates damage to concrete pavements, retaining walls, bridge decks and railings attributable to freeze-thaw cycles is one of the major causes for repair and maintenance works. Water molecules are very small and therefore able to penetrate even the finest concrete pores and capillaries. Once water has entered the capillary system and freezes it will expand in volume and dilate the concrete pore or cavity by exerting hydraulic pressure generated by the expansion. This pressure will slowly – over the span of multiple cycles –

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widen the pores or capillaries. Once the water in the pores thaws it will advance deeper into the concrete where the process is repeated once the water in freezes again and so forth. Damages caused by freeze-thaw cycles are most commonly cracking and spalling of concrete due to progressive expansion of the cement paste. The freeze-thaw effect is drastically enhanced if moisture and deicing salts – used in road maintenance – are present, which can lead to maximum scaling of the concrete surface. Spalling and cracking of the concrete will ultimately expose the embedded reinforcement steel to corrosion due to chloride and water penetration.

Figure 9 Example of freeze-thaw damage on roads and bridge decks

2.6. Concrete deterioration due to chemical attack

A well-hydrated cement paste provides a very alkaline environment in concrete with pH values ranging from 12.5 to 13.5. As a result of the contact between acidic environmental conditions and the concrete this alkaline environment is disturbed and lead to a lowering of the pH level. Depending on the acidity of the attacking chemical concrete deteriorates slower or faster. The effects of concretes under chemical attack always result in an increase of the porosity and permeability, cracking and spalling and subsequently in a loss of strength. The combination of the physical deterioration and persisting exposure to the chemical attack continue and accelerate the deterioration of the concrete over time.

Chemical attacks involve attacks by acidic solutions promoting the formation of soluble calcium salts, insoluble and non-expansive calcium salts and solutions containing magnesium salts. In the following context this document will focus on other chemical attacks that involve the formation of expansive products (due to internal stress), such as sulfate attacks, delayed ettringite formation, alkali-aggregate reaction (AAR) and corrosion.

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Figure 10 Example of concrete damage caused by chemical attack

2.7. Sulfate attack

Sulfate attacks can result either in an expansion and cracking of concrete or lead to a gradual decrease in the compressive strength.

Cracking and spalling allows aggressive and corrosive (ground) water to penetrate more easily as a direct result of increased permeability, which will effectively accelerate the deterioration of the affected concrete. This is also known as external sulfate attack.

A weakening of the concrete is achieved through the detachment of the cement paste from the aggregates, such as caused by delayed ettringite formation (DEF), which is usually considered as internal sulfate attack as it involves sulfate ions contained in the concrete (e.g. cement containing an unusually high sulfate content). DEF causes cracks in the cement paste and the aggregate-cement paste interface resulting from an expansion due to the formation of ettringite around the aggregates. DEF occurs in the late ages of the concrete when sulfate ions released by the decomposition of ettringite are absorbed by calcium-silicate hydrate. Once the sulfate ions are desorbed, the re-formation of ettringite causes expansion that leads to cracking.

2.8. Concrete structures in marine environments

In a marine environment concrete is exposed to a combination of deterioration effects. These include primarily the chemical reaction of seawater with the concrete, penetration of salts and chlorides during wetting/drying conditions, freeze-thaw-cycles in cold climates, corrosion of the reinforcement steel and physical erosion due to wave action. Due to intermingling of these effects concrete structures in marine environments bear higher risks of

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deterioration and special considerations should be taken into account in order to ensure the durability of these structures.

3. Waterproofing with Penetron Admix

Penetron Admix, a 3rd generation crystalline, concrete-enhancing admixture, is the most advanced formula to effectively waterproof concrete structures. It eliminates problems related with 1st and 2nd generation admixtures such as loss of compressive strength and unusually long delays of the setting time.

Penetron Admix can be applied to any commonly-used concrete mix in today’s’ construction industry. It doesn’t have any known incompatibilities with other workability enhancing

admixtures such as retarders or superplastizicers and there are no limitations in regards to the w/c ratio of the concrete to be treated. With dosages rates as low as 0.8% (by weight of cement) it is not only one of the most cost-efficient and economic waterproofing choices, but an effective formula that has been proven in many international laboratory tests and on countless projects worldwide.

Penetron Admix is a non-toxic product and is approved for use in projects involving potable water (NSF 61 approval, European Environmental License). Penetron Admix does not contain any volatile organic compounds (VOC) and is used in green projects acquiring LEED certification points.

When applied to concrete Penetron Admix assists in the hydration process acting as a catalyst to un-hydrated cement particles already existing in the concrete. This already takes place in the early stages of the cement-reaction resulting in the development of internal strength build up compensating to some extent the formation of shrinkage cracks as well as the increase in compressive strength. At the same time a longer workability of the fresh concrete is provided.

3.1. How it works

Penetron Admix is added to the concrete mix at the time of batching at dosage rates between 0.8-1% by weight of cement (alternatively Penetron Admix can be added into the mixing truck on site before the concrete is poured). The activating chemicals of Penetron Admix react with water, calcium hydroxide and aluminum as well as other metal oxides contained in the concrete to form a web of insoluble crystals. These crystals seal all existing capillaries, micro-cracks and voids of up to 0.4mm for the lifetime of the concrete. Once formed, the crystal formations will prevent water, water-borne salts and a wide range of chemicals from entering and moving through the concrete and protect it permanently. Air is still allowed to pass through the crystalline formations allowing the concrete to breathe and avoiding build-up of vapor pressure.

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Penetron Admix will subsequently enhance concrete properties resulting in an increased compressive strength and reduced shrinkage cracks.

In addition Penetron Admix will provide a ―self-healing‖ concrete. In absence of moisture the

activating chemicals remain dormant in the concrete for years. If cracks occur at any time the Penetron Admix components are activated by any penetrating moisture. As a result the chemical reaction will resume automatically and the developing crystals will practically ―self-heal‖ the new crack, sealing it off completely.

Figure 11 How Penetron works

3.2. Features and benefits of Penetron Admix

3.2.1. Permanent concrete protection

Penetron Admix is a permanent application. It becomes an integral part of the concrete by forming insoluble crystals in the capillaries, pores and microcracks in concrete of up to 0.4mm. Once these crystal formations have developed in the concrete matrix they will stay there for the lifetime of the concrete turning the concrete itself into the water barrier. Unlike barrier products (membranes, cementitious coatings) Penetron-treated concrete will remain its waterproofing and protection properties even if the surface is damaged. Penetron Admix does not require re-application.

Figure 12 Scanning Electron Microscope Photograph of

Penetron crystals

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3.2.2. Self-healing concrete

Penetron Admix is an active waterproofing admixture that provides projects with a self-healing concrete. Being a hydrophilic product Penetron Admix reacts with moisture to form crystals in cracks and voids of the concrete. Should new water enter through newly formed cracks in the structure – even years after construction – the chemical reaction of Penetron Admix will resume. Penetron crystal formations will develop and ultimately seal these new cracks as well.

A test performed at the MFPA in Leipzig, Germany1 examined the self-healing behavior of Penetron Admix-treated concrete. In order to simulate the self-healing effects crack-containing concrete cubes were produced by placing new, Admix-treated concrete (containing 1% Penetron Admix by weight of cement) onto already cured concrete (containing 1% Penetron Admix). After curing the two halves were forced apart by wedges to create a joint of 0.2mm, 0.25mm. A 0.1 bar (1m water-column) water pressure was applied at each of the joints and the flow-through of water through at both joints was measured (see figure 13). It was observed that the water-flow through the joints continuously decreased over time. Once the water-flow reached a value of less than 5 cubic centimeters per hour, the pressure was raised to 0.5 bar (5m water-column) and the water-flow through the joint was measured. After the flow was reduced to less than 5 cubic centimeters per hour the pressure was raised to 1.0 bar (10m water-column). In both cases a sealing of the joints was observed.

Figure 13 Test setup, MFPA Leipzig, Germany, 2006

1 MFPA Leipzig GmbH, Germany – Department of Structural Engineering: “Application-technology tests on

concrete test specimens with and without adding the sealing agent Penetron Admix (May 31, 2007)”

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Following tables show the water flow through the joints at different water pressures (0.1 bar, 0.5 bar, 1.0 bar).

Figure 14 Water flow through 0.2mm crack at water pressures of 0.1, 0.5 and 1.0 bar

Figure 15 Water flow through 0.25mm crack at water pressures of 0.1, 0.5 and 1.0 bar

The self-healing properties of Penetron Admix-treated concrete prevent penetration of water, chemicals and other corrosive agents from entering the concrete through cracks that form in the later stage in the lifetime of the structure.

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3.2.3. Corrosion protection of reinforcement steel with Penetron Admix

By sealing the capillaries, pores and microcracks of concrete with insoluble crystal formations Penetron Admix reduces the permeability of the concrete and denies water and corrosive chemicals the entryway into the concrete structure. Water-borne salts, chlorides and other chemicals are prevented from reaching the reinforcement steel and start corrosion by breaking down (lowering of the pH levels) the alkaline surrounding of the concrete and the protective coating of the rebar.

A test performed at the renowned ENCO Laboratory2 clearly shows a reduction of water penetration (reduction of permeability) into Penetron Admix-treated concrete compared to the control concrete.

In the second series of this test concrete samples containing 1% Penetron Admix (by weight of cement) were water cured for 10 days. The samples were then subjected to a water pressure of 9 atm (9 bar) (10 days for the samples with a w/c ratio of 0.65 and 20 days for the samples with a w/c ratio of 0.43). The samples were then again placed in water for an additional 10-20 days until the start of the actual water permeability tests with a pressure of 5 atm (5 bar).

The Penetron Admix-treated samples (w/c=0.65) show a significant improvement in the water penetration compared to the control sample. The table below shows the detailed results.

2 Evaluation of the efficacy of the additives Penetron Admix and Penetron in porous and cracked concretes (second test series); ENCO Laboratory, Italy, 2006

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Figure 16 Excerpt: Permeability of Penetron-Admix-treated concrete vs. control sample (ENCO, 2006)

Apart from isolating the reinforcement steel from the external environment, cured Penetron (Penetron is Portland cement –based) has an alkalinity of around pH 11 and will thus prevent the steel from corroding by adding more alkalinity to the mix. Moreover, by preventing soluble alkaline salts (calcium hydroxide) from being flushed out of the concrete due to water migration and by densifying the concrete matrix to reduce carbon dioxide gas diffusion, Penetron will help to maintain the alkaline environment that is necessary to protect the reinforcing steel.

3.2.4. Protection against chloride penetration

Chlorides are the major factor in precipitating corrosion in concrete and enter the concrete mass usually by migration into the capillary system over time.

Independent testing has established that the chloride content of Penetron Admix itself is very low (<0.10% aggregate3) and its waterproofing effects are not related to chlorides. Penetron-treated concrete was found to be resistant to acidic and alkaline conditions ranging from pH 3 to 114.

3 Electrochemical analysis of a concrete additive “PENETRON ADMIX” according to DIN V 18998 [1], MFPA

Stuttgart, Germany, 2008 4 Testing of Penetron Waterproofing Materials for Chemical Resistance; Shimel and Sor Testing Laboratories Inc.,

Report No. 93-3981, 1993

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International tests have shown that Penetron Admix-treated concretes significantly reduce the penetration of chloride ions into the concrete. In a test according to AASHTO-T-277 undertaking in 20055, Penetron Admix-treated concrete reduced the chloride permeability by more than 80% compared to the control sample.

Figure 17 Excerpt: Chloride permeability of Penetron Admix (AASHTO-T-277: Shimel and Sor, USA, 2005)

In another test6 Penetron Admix-treated concrete was tested for Rapid Chloride Penetration (RCPT) according to ASTM C1202. The results below show a clear reduction of chloride penetration of over 45% between the control sample and the Penetron Admix sample.

Figure 18 Excerpt: Results of the rapid chloride penetration test at Sardar Patel, India, 2009

As proven in the above test reports Penetron significantly reduces chloride ion penetration as it prevents the ingress of salt solutions, which allow chloride ions to migrate through the concrete structure (diffusion).

Structures exposed to cyclic wetting and drying, such as marine structures (bridges, piers, sea walls, etc.) where salt laden media are in direct (or indirect) contact with the concrete, are especially susceptible to chloride ion ingress. Penetron Admix help to protect these structures effectively against chloride penetration and water ingress.

5 Laboratory Tests of Penetron Admix in Concrete, Sor Testing Laboratories, Inc., USA Report No. 05-4070A, 2005 6 Performance evaluation of waterproofing products based on crystallization; Sardar Patel College of Engineering, Mumbai, India, 2009

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Figure 19 Seawall treated with Penetron Admix, Portocel, Aracruz, Brazil

Figure 20 The Capri, Miami Bay, USA. Basement structure treated with Penetron Admix

3.2.5. Protection against carbonation Another factor for corrosion is carbonation. In practice, the atmospheric environment slowly permeates the concrete surface. This carbonation process progressively reduces the pH of the pore solution in the affected area. Where carbonation progresses far enough into the concrete surface to reach the reinforcing bar, corrosion of the re-bar will be initiated. The rate at which carbonation progresses in concrete depends on a number of factors including the humidity of the concrete, exposure conditions, concrete quality and strength, compaction and curing as well as the water/cement ratio of the concrete mix. The water/cement ratio is particularly important. Increasing the water/cement ratio from 0.45 to 0.60 will double the rate of carbonation because of increased porosity. In good quality concrete, the carbonation rate may be negligible while low quality concretes may show 1mm per year. Penetron drastically reduces carbonation by reducing the porosity of the concrete and narrowing the capillary tracts. By producing a stronger, denser concrete the diffusion of carbon dioxide gas will be inhibited and as the crystalline growth blocks and fills the capillary tracts the amount of gas able to penetrate the concrete will be reduced. Recent studies have established that even though the crystal growth structures are breathable, the diffusion of carbon dioxide gas was reduced by 42% when compared to a reference concrete.

3.2.6. Crack bridging ability of Penetron Cracking is an inevitable result of the curing process and increases the permeability of the concrete. The larger the cracks the more susceptible the concrete becomes towards ingress of water and corrosive agents. Penetron will seal shrinkage cracks, pores and capillaries of up to 0.4mm blocking the passage-way into the concrete and protecting it from corrosion and resulting deterioration. Due to the self-healing ability of Penetron products, new cracks are repaired automatically as soon as moisture enters.

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Figure 21 Backscattered Electron Image (BEI) of Penetron crystals forming in a crack7.

Figure 22 Needle-like, elongated Penetron forming in the cracks

In order to demonstrate the crack sealing ability of Penetron tests were undertaken at the ENCO Laboratory8 in Italy.

The tests were performed on 10x10x10cm test cubes with a w/c ratio of ≤0.55 thus prepared:

- curing for 5 days at 20°C and RH >95%; - cracking by means of the Brazilian indirect tensile strength test and inclusion in a

15x15x15 cm test cube with high performance premixed ―betoncino‖ concrete cement;

- curing for 5 days at 20°C and RH >95%; - grinding and sealing with water/Penetron slurry = 0.45 applied along the crack and

then in quantities of 1kg/m2 along the entire surface exposed to water penetration; - curing at 20°C and RH >95% for 2 days, then in water at 20°C for 60 days.

At the end of the 60 days both the cracked test pieces sealed with Penetron and the reference pieces prepared using the same concrete not cracked, underwent a water impermeability test according to the UNI EN 12390-8 standard (3 days at 5atm.). The results of these tests are shown in the table below.

7 Microscopic analysis of the concrete cores from retaining wall at Changi Airport Terminal 3; SETSCO Services

Pte Ltd., Singapore, 2002 8 Evaluation of the efficacy of the additives Penetron Admix and Penetron in porous and cracked concretes (first

test series) C) Effect of Penetron treatment on the surface of structures of low porosity, cracked concrete; ENCO Laboratory, Italy, 2005

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Figure 23 Excerpt: Permeability results of cracked concrete samples treated with Penetron

The surface treatment with Penetron on the cracked test piece totally restored the water tightness, even improving the performance compared to the untreated, undamaged control samples.

In a test performed at OFI laboratories in Vienna, Austria9 test cubes containing horizontal joints were treated with a Penetron coating. An additional layer of 25mm concrete was casted onto the Penetron coating (see figure 34). The samples were then subjected to a water pressure of 7 bar. The results showed that the water penetration into the untreated 25mm top layer only measured 22mm. Due to the crystal growth in the added, upper concrete layer the penetrating water was stopped 3mm before reaching the actual Penetron layer.

Figure 24 OFI sample set-up (Penetron “sandwich-system”)

9 Water penetration of concrete specimen treated with “Penetron” following OENORM B 3303, 2002-09-01; Test

Report No.: 303.897-1; OFI Technologie & Innovation GmbH, Vienna, Austria, 2005

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3.2.7. Increase in compressive strength

When applying Penetron (especially Penetron Admix) a denser mass of the concrete is created by sealing all capillaries and voids with insoluble crystal formations. This usually results in an increase in the compressive strength of the treated concrete.

Tests performed at the University of New South Wales10 in Australia showed that Penetron Admix-treated samples (1% by weight of cement) significantly increased the compressive strength compared to the control samples.

Below are the detailed results obtained in this test campaign according to the Australian Standard AS1012.9:

Concrete Age (day) Compressive Strength (MPa) Ratio of Mix-P to Mix-C Mix-P

(Penetron Admix) Mix-C

(control sample) 3 23.0 16.7 1.37 7 31.4 24.2 1.30

28 42.5 33.2 1.28 91 46.8 38.2 1.22

The compressive strength of the Mix-P was 1.22 to 1.37 times of that of the control Mix-C at ages between 3 days to 91 days despite the slump of Mix-P (130mm) being much higher than that of Mix-C (80mm). It was apparent that the use of the Penetron Admix in concrete significantly increased the concrete strength. The increase in compressive strength by the Penetron Admix was proportionately greater at the early ages of 3 and 7 days. An important benefit of the rapid early strength gain is permit striping of formwork earlier and to speed up the construction process.

The increase in compressive strength depends to a great extend on the porosity of the concrete. In more porous types of concrete the increase in compressive strength is usually expected to be higher than in more dense types of concrete. As such the change in compressive strength varies between different types of concrete. In any case Penetron products will not negatively affect the compressive strength of the concrete.

3.2.8. Resistance against high water pressure

Penetron products effectively seal concrete pores, capillaries and microcracks and make them impermeable against water ingress and chemical attacks. Penetron protects concrete structures in under extreme conditions and waterproofs concrete even against high hydrostatic pressures.

10

The Australian Centre for Construction Innovation University of New South Wales: “Properties of type GP cement concrete modified with Penetron Admix”; ACCI Ref.No. 58324, 2002

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A test executed at the IPT Laboratories in Sao Paulo, Brazil11 examined the water penetration of water under pressure into porous Penetron Admix-treated concrete samples (20MPa, w/c=0.54, 1% Penetron Admix by weight of cement) according to Brazilian Standard NBR 10.787/94.

The concrete samples were casted and cured in water for 28 days.

Water pressures were applied over the period of one week:

Day 1-2: 0.1 MPa (1 bar) Day 3: 0.3 MPa (3 bar) Day 4-7: 0.7 MPa (7 bar)

After the first week the water penetration into the sample was observed. The sample was then dried and the test repeated for a second, third and fourth week. After four weeks of applied water pressures of up to 7 bar all microcracks, pores and capillaries had been sealed by Penetron Admix and no further water was able to penetrate into the samples.

11

Penetration of water under pressure; Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, Brazil, 2007

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After one week of water pressure a water penetration of approximately 75% into the sample can be observed. This is possible, because the crystals in the sample have not fully formed yet. The water in the capillaries is used to grow the crystals further.

After two weeks a significant reduction in the water penetration can be noticed with the crystals continue to form inside the concrete.

After the third week, the water penetration into the sample has decreased again by almost 50% compared to the results of the week before.

After the fourth week of applied water pressure no water is able to penetrate into the capillaries of the Penetron Admix treated concrete. The crystals have now formed completely and sealed the concrete withstanding the water pressure.

The above test shows Penetron Admix-treated concrete completely dry under hydrostatic pressures of up to 7 bar. A test campaign at the University of Bologna12, Italy in 2005 tested Penetron Admix against a water pressure of 2000 kPa (20 bar). The Penetron-treated sample shows significant reduction the permeability (water penetration) compared to the control sample.

12

Determination of the water absorption at atmospheric pressure and under pressure of a total of 42 cylindrical concrete test pieces at the Laboratorio del Consorzio Cave (Quarry Consortium Laboratory) of Bologna; University of Bologna – Department of Earth, Geological and Environmental Sciences, Italy, 2005

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Figure 25 Excerpt: Test results for Penetron Admix under 20 bar head water pressure, University of Bologna, Italy, 2005

The possibility to withstand high hydrostatic pressure makes Penetron Admix an effective solution for concrete structures such as hydroelectric dams, large water tanks, sea walls, tunnels, etc.

3.2.9. Chemical resistance

Penetron not only effectively waterproofs concrete structures, but also protects concrete against chemical attacks of various chemicals with a pH range from 3-11.

Accordant tests were undertaken at the University of Bologna13, Italy where Penetron-Admix treated concrete samples were exposed to various chemical solutions including diluted hydrogen chloride (HCldil), diluted sulfuric acid (H2SO4dil), a combination of the former, calcium chloride (CaCl2) and sodium hydroxide (NaOH).

For this test on April 4, 2005 ten (10) cylindrical concrete test pieces, divided into two batches, each consisting of 5 pieces, were prepared.

1st batch: ―Concrete B‖: defined as white, i.e. concrete made without adding Penetron Admix

2nd batch: ―Concrete PA‖: defined as concrete made adding Penetron Admix in percentages

of 2% by weight of the cement.

Both control and treated concrete samples had a w/c = 0.45.

13

Verification of resistance to chemical attack on ten (10) cylindrical concrete test pieces at the Laboratorio del Consorzio Cave (Quarry Consortium Laboratory) of Bologna; University of Bologna – Department of Earth, Geological and Environmental Sciences, Italy, 2005

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The concrete to be tested was prepared at the Laboratorio del Consorzio Cave (Quarry Consortium Laboratory) of Bologna and cured there for 28 days in a climatic test chamber at 20 ± 2°C and RH 95% ±3 RH. They were then conditioned in air with RH of 65% ±3 at a temperature of 20 ± 2°C until a constant density was reached, evaluated by 2 weighing cycles carried out at 24-hour intervals and with a difference in density inferior to 0.1%.

The laboratory wanted to verify the resistance to chemical attack of these samples using solutions containing different hydrogen ion concentrations according to test standard UNI 7928 and 8019. Observations were carried out after 7 and 28 days of exposure.

Figure 26 University of Bologna: Chemical resistance test - Test set up

For the visual evaluation of chemical resistance standard UNI EN ISO 10545 -13/7 ―Determination of chemical resistance – unglazed tiles‖ was applied.

As the table below shows Penetron Admix treated concrete did not permit any of the tested solutions to penetrate into its surface. The samples resisted all solutions with a pH value between 3 and 11 in constant contact and improved the condition of the samples in contact with diluted hydrogen chloride (HCldil), diluted sulfuric acid (H2SO4dil), a combination of both diluted hydrogen chloride and diluted sulfuric acid, where penetration into the surface was observed at the control sample.

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Figure 27 University of Bologna: Chemical resistance test - results

Due to its chemical resistance Penetron is protecting the concrete structures of various projects around the world involving contaminated waters, such as sewage treatment and waste water treatment plants, chemical storage tanks.

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Figure 28 Milan South Waste Water Treatment Plant, Italy

Figure 29 SABESP Sewage Treatment Plant, Brazil

3.2.10. Resistance to freeze-thaw cycles

One major factor for deterioration of exposed concrete structures in cold climates (such as concrete bridges, roads, etc.) is the continuous freezing and thawing of concrete. Over time freeze-thaw cycles will increase the permeability and allow corrosive agents to penetrate resulting in corrosion damage and leading up to the failure of the structure. Freeze-thaw-cycles directly affect the durability of concrete.

Independent tests undertaken at Sor Testing Laboratories14 show a significant reduction of weight loss of Penetron-Admix treated concrete compared to the control sample.

The treated concrete contained 16% fly ash and Penetron Admix was dosed at 1% by weight of cementitious materials (cement and fly ash). The control sample consisted of plain concrete without Penetron Admix.

The specimens were then subjected to a 3% sodium chloride solution in 25 cycles of freeze-thaw (according to the New York Department of Transportation Method 502-3P).

Mix I.D. Average % Weight Loss (*) No. 1 – Control 4.97

No. 2 – Penetron Treated 0.74 (*) Average of duplicate specimens

3.2.11. Compatibility with commonly-used concrete mix designs (Penetron Admix)

Penetron Admix has been specified and performed in numerous concrete mix formulations around the world. It can be applied to any commonly-used concrete mix in today’s

construction industry. Penetron Admix does not have any known incompatibilities with other

14

Laboratory Tests of Penetron Admix in Concrete, Sor Testing Laboratories, Inc., USA Report No. 05-4070A, 2005

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workability-enhancing admixtures, such as retarders or superplastizicers. There are no limitations in regards to the water/cement ratio of the concrete to be treated.

Penetron Admix treated concrete can contain Portland cement-substitutes such as pozzolans, fly-ash, slag, silica fume and similar. The crystal reaction in these types of concrete will still take place as Penetron Admix, being a Portland cement-based product, contains the reactive ingredients needed for its reaction to develop crystals in the microcracks and capillaries.

3.2.12. Prevention of Alkali-Silica-Reaction (ASR)

As discussed in chapter 2.4., alkali-silica-reaction (ASR) can significantly reduce the durability and strength of concrete. Concrete designers need to limit the alkali content of the mix by selecting the right type of cement and non-reactive aggregates.

A simpler way to reduce the risk of ASR is to incorporate a mature crystalline admixture, such as Penetron Admix, into the concrete mix. This will ensure the concrete is waterproofed in-depth and deny the ASR the necessary water for the reaction to take place. Penetron Admix has shown in a test at the MFPA-Leipzig, Germany15 that cracks will self-heal upon when presented with water. Many other tests have proven the ability of Penetron crystals to waterproof the capillary structure inside concrete. Further, Penetron Admix is certified by the MPA Stuttgart, Germany16 to correspond to DIN V 18998 and as such has no negative influence on the embedded steel.

3.2.13. Limitations

Despite the large number of benefits of crystalline waterproofing systems a few concerns need to be given to the limitations of the performance of this system:

Insufficient surface preparation (coating application)

When Penetron is applied as a surface coating, a thorough surface preparation including the repair of all cracks larger than 0.4mm, faulty concrete (such as honeycombs, form-tie holes, etc.), the cleaning of the surface (in in order to dampen and roughen the surface and to ensure an ―open-capillary-system‖) is key to a successful application of crystalline

waterproofing systems that are applied by brush or spray.

3.2.13.1. Cold joints

15

MFPA Leipzig GmbH, Germany – Department of Structural Engineering: “Application-technology tests on concrete test specimens with and without adding the sealing agent Penetron Admix (May 31, 2007)” 16

MPA Stuttgart Otto-Graf Institute, University of Stuttgart, Germany: “Electro-chemical tests of a concrete admixture (Penetron Admix) according to DIN V 18998: 2002-11”, 2007

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Cold joints can be considered as artificial cracks. The widths and voids in cold joints can exceed those of a usual concrete capillary or microcracks and therefore need to be treated separately either with a crystalline repair system (Penecrete/Penetron) or Penebar SW waterstops.

3.2.13.2. Active leaks

Active leakage (through cracks) needs to be stopped prior to application and repaired separately with the Penetron repair system (Peneplug, Penecrete, Penetron Inject).

3.2.13.3. Concrete defects

Concrete defects such as honeycombs, form-tie holes, etc. lead to voids in the concrete that are beyond the width of a usual capillary or microcracks and therefore need to be repaired separately with the Penetron repair system.

3.2.13.4. Structural cracks

Structural cracks are cracks with a width larger than 0.4mm and therefore need to be repaired either prior to the application of Penetron as a coating system or after application (Penetron Admix) if they do not seal up after an observation period of 4-6 weeks.

3.2.13.5. Exposed concrete structures (thermal cracks)

Penetron is not recommended as a stand-alone solution for directly exposed concrete structures. Thermal cracks are a result of concrete directly exposed to high, sudden temperature differences (e.g. expansion of the concrete exposed to extreme heat during daytime, which contracts as a result of falling and cooler temperatures during night time). This may lead to movement within cracks and crack widths of up to >2mm. Penetron crystals are rigid and are not designed to compensate for such kind of movement in cracks.

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4. At one glance - Benefit overview System benefits Benefits to property owners/contractors

Increases the durability of concrete Protects concrete for a lifetime

(permanent application) Provides a ―self-healing‖ concrete

(self-heals cracks up to 0.4mm) Resistance to high hydrostatic

pressure (20 bar) Increases compressive strength Resists chemical attack (pH 3-11) Reduces chloride penetration and

carbonation Prevents Alkali-Silica-Reaction (ASR) Prevents reinforcement steel from

corrosion Non-toxic (potable water approved) Green product (contains zero VOC) Can be used with any commonly

used mix design (no limitations towards w/c ratio or cement content)*

Low dosage rates (0.8% by weight of cement)*

Ease/versatility of application Protection remains intact when

surface is damaged Does not require any other form of

waterproofing or additional protection of the system

Allows concrete to ―breathe‖ Penetrates deeply into the concrete** Can be applied from the positive or

negative side** Can be applied to moist or green

concrete** Compatible with glues and surface

coatings** Internationally renowned

waterproofing brand with extensive track record (proven system)

Provides time and cost savings on projects

Cost effective Permanent waterproofing system No maintenance Increases the quality of the concrete

for structural performance and integrity

Increases usage of infrastructure Eliminates down-time and costs

associated with maintenance and repairs

Unmatched technical support Reduces application errors

associated with installation of other systems

Improves pouring and placement of concrete

Contributes to LEED projects (accrual of green points)

*Penetron Admix / **Penetron/Penetron Plus

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5. Comparison of Penetron products with other waterproofing systems Penetron/

Penetron Plus Penetron Admix

Membranes (Positive side)

Other surface applied Products

Description Cementitious-based chemical that will penetrate surfaces to form insoluble crystal formations deep inside the capillaries and voids of concrete

Cementitious admixture added to the concrete at the time of batching to form insoluble crystals throughout the capillary system of concrete

Liquid and sheet applied bitumen and polymers affixed to the concrete surface to form a barrier against water ingress

Materials applied to the concrete surface containing mainly water repellents and sealants

Resistance to hydrostatic water pressure

Improves with time

Tested of up to 16 bar head water pressure

Improves with time

Continuous self-healing ability

Initiates full hydration

Protection breached by any pinhole or seam

Will require replacement once leaking

Reduces initial absorption, but will deteriorate over time Limited resistance

to hydrostatic pressure

Protection of reinforcement steel

Prevents corrosion by stopping passage of penetrating water, chlorides and other corrosive agents

Permanent protection

Prevents penetration of water, chlorides and other corrosive agents

No negative side protection

Prone to leak at joints and seams

No negative side protection Limited protection

especially under higher water pressure

Crack self-healing ability

Will re-activate in the presence of moisture to seal new cracks even years after application

Will re-activate in the presence of moisture to seal new cracks even years after application

No self-healing ability

No self-healing ability

Crack resistance

Rigid material, cannot withstand excessive transformation, but self-heals cracks of up to 0.4mm

Reduces cracking in plastic and curing stage

Self-heals cracks of up to 0.4mm in the presence of moisture

Can withstand excessive transformation Deteriorating over

time (loss of protection)Concrete ―unprotected‖ if leaks occur

No durability at crack locations

Deteriorating over time (loss of protection)

Freeze/thaw durability

Improves durability by preventing water ingress through cracks and pores

Improves durability by preventing water ingress through cracks and pores

Deteriorating over time (loss of protection)Concrete ―unprotected‖ if leaks occur

Deteriorating over time (loss of protection)Concrete ―unprotected‖ if leaks occur

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Repair requirements

Easily repaired from positive or negative side (if required)

Easily repaired from positive or negative side (if required)

Difficult to repair Difficult to identify

problem areas May require total

removal and repair

Expensive and sometimes impossible due to accessibility

Repairs may require removal of previous materials

Application Applied by brush/spray onto positive or negative side of old/new concrete

Dry-shake application onto horizontal, freshly placed concrete

Added to the concrete at the time of batching

No additional application required

Liquids: brush or spray application

Sheets: glued, welded or torched to the concrete surface

Correct joints/seams application critical to performance

Only applied to positive side

Substrate profile critical to performance

Surface preparation

Needs coarse, water saturated, clean surface with an ―open-capillary system‖ for brush or spray application

No surface preparation for dry-shake application

No surface preparation

Clean surface Dry surface Smooth surface

Needs surface preparation depending on product requirements

Construction schedule

Can be applied during concrete finishing or anytime after

Added to fresh concrete at the time of batching

Saves up to 50% time and construction costs

Must be applied after completion of structural work

Requires protective cement mortar

Some materials require 28 days cured concrete for application

Similar scheduling as membranes

Sub-surface drainage system

Not required Not required Might require drainage under high hydrostatic pressure

Requires drainage under high hydrostatic pressure

Additional coatings

Can be finished with coating, tiles, etc.

Does not affect coatings

Adhesion excellent for coatings of tiles

Require protective mortars prior to finishes

May require special preparation prior to finishes

Maintenance Not required Repairs might be required once in the case of

Costly replacement generally required

Re-application required under high hydrostatic conditions

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structural cracks of concrete defects after application

Service life Permanent and improves with time

Permanent; self-healing of new cracks even years after application

Deteriorating over time

Damages during backfilling, plumbing

Surface damage will result in loss of protection

Best when first applied

Deteriorate over time

Vulnerable to surface damage

5.1. Comparison between Penetron and hydrophobic pore blockers

Penetron Pore blockers

Allows concrete to breathe, vapor to escape the structure

Does not let concrete breathe, allowing vapor pressure build up

High performance waterproofing product designed to resist high hydrostatic pressure proven up to 16 Bar

Good for damp proofing or water splash resistance with low hydrostatic water pressure resistance up to 1.4 Bar

Does not affect the heat resistance of the concrete and will only increase it

Due to bituminous nature of these products, their effect on the heat resistance of the concrete should be investigated before use

Does not negatively affect the hydration process of the concrete

Completely stops water movement within concrete, as such internal self-desiccation may occur or imbibing water cannot enter.

In both cases a portion of cement cannot be hydrated completely

Penetron dramatically increases the autogenous healing ability of concrete

May decrease the autogenous healing capacity of concrete. This should be investigated before use

Increases compressive strength of concrete Effect of these products on initial and final strength of concrete should be investigated before use

Does not affect the amount of reinforcement steel specified

May require additional reinforcement steel

Does not affect the setting time of the concrete when specified properly

Effects on the setting time of concrete need to be investigated before use

Provides chemical, carbonation, sulfates, chloride etc. protection

Resistance against chemical attack should be investigated before use

Does not negatively affect the performance of Construction joints will require special treatment to

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construction joints break the water- repellent effect of these products

Low dosage of 0.8% of cement contents in the mix will suffice

Very high dosage required to reach their effect

Economical solution Usually very expensive solution, partly because of high dosage required

Works very effectively even on low strength concrete

A minimum of 350 kg of cement is required for these products to be effective, Water / cement ratio and slump need to be tightly controlled to comply with manufacturer’s published limitations

Self heals cracks of 0.4mm and more throughout the life of the concrete

Blocks pores passively, no known self healing effect on concrete

Will reactivate after many years if new cracks develop to stop leaks

No reactions

Long term effects on concrete have been proven over 24 years

Long term effects on concrete should be investigated before use

6. Application instructions – Penetron Admix

6.1. Description

Penetron Admix (integral crystalline waterproofing admixture) is added to the concrete mix at the time of batching. Penetron Admix consists of Portland cement, very fine treated silica sand and various active, proprietary chemicals. These active chemicals react with the moisture in fresh concrete with the by-products of cement hydration to cause a catalytic reaction, which generates a non-soluble crystalline formation throughout the pores and capillary tracts of the concrete. Thus the concrete becomes permanently sealed against the penetration of water or liquids from any direction. The concrete is also protected from deterioration due to harsh environmental conditions. Note The Penetron Admix has been specially formulated to meet varying project and temperature conditions (see Setting Time and Strength). Consult with a Penetron Technical Representative for the most appropriate Penetron Admix for your project.

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6.2. Dosage Rate

Penetron Admix: 0.8% by weight of cementitious materials minimum. Consult with Penetron’s Technical Department for assistance in determining the appropriate dosage rate and for further information regarding enhanced chemical resistance, optimum concrete performance, or meeting the specific requirements and conditions of your project.

6.3. Mixing Penetron Admix must be added to the concrete at the time of batching. The sequence of procedures for addition will vary according to the type of batch plant operation and equipment. Following are some typical mixing guidelines.

6.3.1. Ready Mix Plant – Dry Batch Operation Add Penetron Admix in powder form to the drum of the ready-mix truck. Drive the truck under the batch plant and add 60% - 70% of the required water along with 300-500 lbs (136-227 kg) of aggregate. Mix the materials for 2-3 minutes to ensure the Admix is distributed evenly throughout the mix water. Add the balance of materials to the read-mix truck in accordance with standard batch practices.

6.3.2. Ready Mix Plant - Central Mix Operation Mix Penetron Admix with water to form a very thin slurry (e.g. 40 lbs (18 kg) of powder mixed with 6 gallons (22.7 l) of water). Pour the required amount of material into the drum of the ready-mix truck. The aggregate, cement and water should be batched and mixed in the plant in accordance with standard practices (taking into account the quantity of water that has already been placed in the ready-mix truck). Pour the concrete into the truck and mix for at least 5 minutes to ensure even distribution of the Penetron Admix throughout the concrete.

6.3.3. Precast Batch Plant Add Penetron Admix to the rock and sand, then mix thoroughly for 2-3 minutes before adding the cement and water. The total concrete mass should be blended using standard practices. Note It is important to obtain a homogeneous mixture of Penetron Admix with the concrete. Therefore, do not add dry Admix powder directly to wet concrete as this may cause clumping and thorough dispersion will not occur. For further information regarding the proper use of Penetron Admix for a specific project, consult with a Penetron Technical Representative.

6.3.4. Technical Services For more instructions, alternative application methods, or information concerning the compatibility of the Penetron treatment with other products or technologies, contact the

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Technical Department of ICS Penetron International Ltd. or your local Penetron Representative.

6.4. Setting time and strength The setting time of concrete is affected by the chemical and physical composition of ingredients, temperature of the concrete and climatic conditions. Retardation of set may occur when using Penetron Admix. The amount of retardation will depend upon the concrete mix design and the dosage rate of the Admix. However, under normal conditions, the Admix will provide a normal set concrete. Concrete containing Penetron Admix may develop higher ultimate strengths than plain concrete. Trial mixes should be carried out under project conditions to determine setting time and strength of the concrete.

6.5. Limitations When incorporating Penetron Admix, the temperature of the concrete mix should be above 40°F (4°C).

7. Application instructions – Penetron

7.1. Description Penetron is a surface-applied, integral crystalline waterproofing material, which waterproofs and protects concrete in-depth. It consists of Portland cement, specially treated quartz sand and a compound of active chemicals. Penetron needs only to be mixed with water prior to application. When Penetron is applied to a concrete surface the active chemicals combine with the free lime and moisture present in the capillary tracts of the concrete to form an insoluble, crystalline structure. These crystals fill the pores and minor shrinkage cracks in the concrete to prevent any further water ingress (even under pressure). However, the Penetron will still allow the passage of vapor through the structure (i.e. the concrete will be able to ―breathe‖). In addition to waterproofing the structure, Penetron protects concrete against seawater, wastewater, aggressive ground water and many other aggressive chemical solutions. Penetron is approved for use in contact with potable water, and is therefore suitable for use in water storage tanks, reservoirs, water treatment plants…etc. Penetron is not a decorative material.

7.2. Consumption Water retaining structures, internal concrete wall surfaces: Two coats of Penetron at 1.25-1.5 lb/sy (0.7-0.8 kg/m²) or one coat at 2.5 - 3 lb/sy (1.4-1.6 kg/m²) applied with brush or spray.

7.2.1. Construction slabs Penetron at 2 lb/sy (1.1 kg/m²) applied in one slurry coat to hardened concrete or dry sprinkled and trowel applied to fresh concrete when this has reached initial set.

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7.2.2. Construction joints Penetron at 3 lb/sy (1.7 kg/m²) applied in slurry or dry powder consistency immediately prior to placing the next lift/bay of concrete. Alternatively Penebar SW type waterstops can be applied.

7.2.3. Blinding concrete Penetron at 2.5 lb/sy (1.4 kg/m²) applied in slurry or dry powder consistency immediately prior to placing the overlying concrete slab.

7.3. Surface Preparation All concrete to be treated with Penetron integral crystalline waterproofing must be clean and have an ―open‖capillary system. Remove laitance, dirt, grease, etc. by means of high pressure water jetting, wet sandblasting or wire brushing. Faulty concrete in the form of cracks, honeycombing, etc. must be chased out, treated with Penetron and filled flush with Penetron Mortar. Surfaces must be carefully pre-watered prior to the Penetron application. The concrete surface must be damp but not wet.

7.4. Mixing Penetron is mechanically mixed with clean water to a creamy consistency or that resembling thick oil. Approximate mixing ratio is 2 parts water to 5 parts Penetron powder (by volume). Mix only as much material as can be used within 20 minutes and stir mixture frequently. If the mixture starts to set do not add more water, simply re-stir to restore workability.

7.5. Application

7.5.1. Slurry consistency Apply Penetron in one or two coats according to specification by masonry brush or appropriate power spray equipment. When two coats are specified apply the second coat while the first coat is still ―green‖.

7.5.2. Dry powder consistency (for horizontal surface only) The specified amount of Penetron is distributed in powder form through a sieve and troweled into the freshly placed concrete once this has reached initial set.

7.6. Post treatment The treated areas should be kept damp for a period of five days and must be protected against direct sun, wind and frost, by covering with polyethythene sheeting, damp burlap or similar.

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Note Do not apply Penetron at temperatures at or below freezing. Penetron cannot be used as an additive to concrete or plasters. (Penetron Admix should be considered for these applications).

8. Application instructions – Penetron Plus

8.1. Description Penetron Plus is a unique integral crystalline chemical treatment for the waterproofing and protection of concrete. Penetron Plus has been specially formulated for dry-shake applications on horizontal concrete surfaces where greater impact and abrasion resistance is required. Packaged in the form of a dry powder compound, Penetron Plus consists of Portland cement, various active proprietary chemicals, and a synthetic aggregate hardener that has been crushed and graded to particle sizes suitable for concrete floors. Penetron Plus becomes an integral part of the concrete surface thereby eliminating problems normally associated with coatings (e.g. scaling, dusting, flaking and delamination).The active chemicals react with the moisture in the fresh concrete causing a catalytic reaction, which generates a non-soluble crystalline formation within the pores and capillary tracts of the concrete.

8.2. Coverage Under normal conditions, the coverage rate for Penetron Plus is 1 lb per sq yard (0.6 kg per m²), depending on the degree of abrasion resistance required. Note Under heavy traffic conditions or where even greater abrasion resistance is required, consult a Penetron Technical Representative for a recommendation that meets your specific needs.

8.3. Application Procedures 1. Fresh concrete is placed, consolidated and leveled. 2. Wait until concrete can be walked on leaving an indentation of 1/4‖–1/3‖ (6-9 mm). Concrete should be free of bleed water and be able to support the weight of a power trowel. Then, float open the surface. 3. Immediately after floating open the surface, apply one-half of the dry shake material by hand or mechanical spreader. The dry shake material must be spread evenly. 4. As soon as the dry shake material has absorbed moisture from the base slab, it should be power floated to the surface. 5. Immediately after power floating, apply remaining dry shake material at right angles to the first application. 6. Allow remaining dry shake material to absorb moisture from the base slab and then power float the material into the surface. 7. When concrete has hardened sufficiently, power trowel surface to the required finish.

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8.4. Curing Curing is important and should begin as soon as final set has occurred but before surface starts to dry. Conventional moist curing procedures such as water spray, wet burlap or plastic covers may be used. Curing should continue for at least 48 hours. In hot, dry sunny conditions consult manufacturer for specific instructions. In lieu of moist curing, concrete sealers and curing compounds meeting ASTM C-309 may be used. Note It is common that edges of a slab wall will set up earlier than the main body of concrete. Such edge areas can be dry-shaked and finished with hand tools prior to proceeding with application of the main body of concrete. For the best results when applying dry shake materials, the air content of the concrete should not exceed 3% (a high air content can make it difficult to achieve a proper application). If a high entrained air content is specified (e.g. for concrete that will be exposed to freezing and thawing), contact the Technical Department of Penetron International Ltd. for further application information. In hot, dry, or windy conditions, it is advisable to use an evaporation retardant on the fresh concrete surface to prevent premature drying of the slab. Chronic moving cracks or joints will require a suitable flexible sealant. For certain concrete mix designs, we recommend a test panel be produced and evaluated for finishing. (For example, high performance concrete with a low water/cement ratio, air entrainment, super plasticizers, or silica fume may reduce bleed water and make the concrete more difficult to finish).

8.5. Technical Services For more instructions, alternative application methods, or information concerning the compatibility of the Penetron treatment with other products or technologies, contact the Technical Department of Penetron International Ltd. or your local Penetron representative.

9. Contact and Disclaimer

Penetron products are exclusively manufactured by ICS Penetron International Limited located at 45 Research Way, Suite 203, East Setauket, NY 11733, USA.

Penetron products are distributed and applied through a global network of authorized distributors and trained applicators. Please consult with a Penetron representative prior to using and applying Penetron products for technical assistance and support.

All referenced test reports in this document are available on request from ICS Penetron International Ltd.