Treatments to Improve Concrete Performance - AIA
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Treatments to Treatments to improve the improve the performance of performance of Concrete Concrete
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The intent of this presentation from W. R. MEADOWS is to provide the most current information available to explain the basics of cement hydration, and to introduce the various types of floor treatments and curing compounds available. The goal of this presentation is to help the specifying agency and end-user identify the correct material for the project. This program is registered with the AIA/CES for continuing professional education. The course earns one AIA credit.
Transcript of Treatments to Improve Concrete Performance - AIA
Treatments to Treatments to improve the improve the
performance of performance of ConcreteConcrete
Lets start with the basics of concrete:
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Just exactly what is CONCRETE?
You Dummy, It wouldn’t
hurt! Cement is a powder
… I was running
and fell on the
Cement ….
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Definitions•Cement = Powder
•Cement + Water = Paste
•Paste + Sand = Mortar
•Mortar + Stone = Concrete
A chemical reaction takes places when the water is mixed with the cement
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The chemical reaction starts a crystal-type growth in the cement.
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This is the critical point…If the cement does not get enough water, the reaction stops and the
concrete will not reach its designed strength
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500
1000
1500
2000
2500
3000
Strength
DesignedStrengthStrength w/omoistureRapid moistureloss
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The moisture must be available to the cement for 21 days.
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Thermal cracking
Hair checking
Shrinkage cracks
In addition to strength loss, there may be:
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Laymen's terms please…..
“CURE” THE CONCRETE
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Effect of CuringEffect of Curing
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20
40
60
80
100
120
140
100 200 300 400
Age, Days
% o
f 28
day
val
ue
Moist Cure
Not Cured
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OK
OK
OK
OK
OK
OK
OKOKOK
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OKI get it….
I need to cure the concrete.
How do I do it?
CURING METHODS
• BURLAP, COTTON MATS, RUGS, OR OTHER MOISTURE-RETAINING FABRICS
• PLASTIC SHEETS
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Lets talk about
water-cure
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Water cure can lead to:
The most economical method of
curing a slab is with a curing
compound
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The trick is to select and specify the appropriate compound for the
project
TYPES OF PRODUCTS
MEMBRANE CURING COMPOUNDS
CURING & SEALING COMPOUNDS
TYPES OF PRODUCTS
CONCRETE SEALERS & EXPOSED AGGREGATE SEALER
CONCRETE DENSIFIERS & CHEMICAL HARDENERS
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WOW – What does it all mean?
ASTM C 1315
ASTM C 309
AASHTO M 148
FAA P-610
F.S. TT-C-800
Is there a specification?
ASTM C 309TYPE 1 (NON- Pigmented)TYPE 2 (White Pigmented)CLASS A OR CLASS BApplication rate 200 SF/GALFilm dries in 4 Hours or less
WATER RETENTION - 0.55 KG/M² (Type 2) MIN. 60% REFLECTANCE
VOC Content less than 350 GPL
Federal SpecificationTT-C-800
Specification has been replaced with the newer ASTM 1315
specification
ASTM C- 1315TYPE 1 or TYPE 2
Different classes… Not by solids type
CLASS A - NON YELLOWING
CLASS B - MODERATE YELLOWING
CLASS C - SEVERE DARKENING
GENERAL REQUIREMENTS
MIN. 25% SOLIDSREFLECTANCE 65% MIN
(versus 60% with c 309)
NOT MORE THAN 0.40 Kg/m² in72 HRS (versus .55 with C 309)
Dry time is less than 4 hoursPULL-OFF STRENGTH 145 psi
VOC Content 700 GPL or less
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FOUR Different Kinds of Concrete
BookCrete - Architect
LabCrete - Chemist
RealCrete – Ready Mix Driver
LegalCrete – Costs Money
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Lets look at it as steps
Sodium Silicates
Cures & Sealers
Dissipating Membrane
DENSIFIER Sealers
ASTM C 309
ASTM C 1315
ASTM ?
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Which steps do I take?
What Kind of floor do you require on your project?
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Radical ConceptChallenge is to specify the
right product for the project.
Not specify “C-309”
Residential Floor slab
Driveway
Sidewalks
Sodium SilicatesCuringHardeningDustproofing Compound
Densifier and Chemical Hardeners
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“I just have to meet a specification”
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Next StepNext Step
Sodium Silicates
Dissipating Membrane
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Dissipating Cures
Curb & Gutter
Sidewalks
Driveways
General areas
DOT applications
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Pigmented Curing Pigmented Curing CompoundsCompounds
Highways
RunwaysMunicipal Streets
Median Barriers
Check with your local Rep for the products used in your State
Typically Large volume
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Next StepNext Step
Sodium Silicates
Dissipating Membrane
Cures & Sealers
SPECIFICATIONS:
ASTM C 309 Type 1, Class BASTM C 1315, Type 1, Class
A•CLASS A - NON YELLOWING
WILL NOT YELLOW FROM SUNLIGHT
Stains wiped clean
DO NOT
Seal over any Stains. They will be magnified
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CAUTIONCAUTION
Blushing can occur
Avoid application in direct sunlight
Watch DEW POINT @ 60% Relative Humidity
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Cure & Anti-Spall
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White Pigmented Cure & Seal
Poly Alpha Methyl Styrene
(PAMS for short)
Normally used on Bridge Decks @ DOT level
Exposed Exposed Aggregate Aggregate
sealersealer
Pay attention to the Pay attention to the ClassClass
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The top Step
Sodium Silicates
Cures & Sealers
Dissipating Membrane
DENSIFIER
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“I want the best floor available”
High Solids Silicates
PENETRATING
PRODUCES A FLOOR WHICH IS “SELF-POLISHING”
SUPERIOR ABRASION RESISTANCE
TOUGHER THAN SURFACE SEALERS (Not a film on the surface of the concrete)
INDUSTRIAL PLANTSPARKING STRUCTURESWAREHOUSESAIRPORTSSEWAGE & WATER TREATMENT PLANTSCHEMICAL & FOOD PROCESSING PLANTSREFINERIES & ARENAS
DESIGNED FOR USE IN
MAY BE USED ON NEW OR EXISTING CONCRETE
May be applied to new concrete after the final troweling
OLD CONCRETE FREE OF OIL &CONTAMINANTS
Application Guide Apply using commercial spray equipment Scrub it into surface utilizing broom/mechanical scrubber Keep surface wet for minimum of 30 minutes (forms a gel) Sprinkle with water prior to final buffing
Application Guide
Remove all excess water & hardener & flush surface after completion of application
Features & Benefits (review)
Chemically reacts with the concrete to harden surface Increases abrasion resistance Improves chemical resistance Reduces permeability Provides an integral seal within the pore structure
Features & Benefits
Improves resistance to staining and markingThe heavier the use of the floor, the harder the surface getsProduces dust free surface
Environmentally friendly
Target Areas
Warehouse stores Heavy traffic areas Arenas & Convention Centers Warehouse Facilities Food Processing Plants
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Application is a KEY consideration….
This is not a spray and forget material
Applying – Garden type sprayer
Mechanical Scrubber
Keep surface wet
Remove Excess
Polished
Un-Polished
Evaporation Reducer
Other Category treatments that aid
the performance
Features/Benefits
Reduces surface moisture evaporation Eliminates or reduces crusting, stickiness and underlying sponginess Reduces and, in many instances eliminates plastic-shrinkage cracking and wind crustingAllows lower slump and lower unit water content in concrete used for flatwork
Features & Benefits
Increases the amount of surface handled per finisher
Encourages the use of air-entrained concrete, required for durability and workability
Timing of various finishing operations is less critical, thus reducing overall cost
Finishing aid for use with polymer concrete or silica fume products
Application
Apply with pressure sprayer
Agitate material in original container and delute one part to nine parts water
Spray surface lightly and uniformly immediately after screeding fresh concrete
Proceed with bull floating----repeat spraying procedure whenever concrete begins to prematurely set
Forms a monomolecular film
Limitations
Not a curing compound
Reduces evaporation only while concrete is in its plastic state
Don’t apply during any finishing operation nor should it be worked into the concrete surface
Protect from freezing
EPA AIM VOC Ruling
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Bituminous Coatings and Mastics Concrete Curing Compounds Concrete Curing and Sealing Compounds Form Release Compounds Primers and Under coaters Waterproofing Sealers and Treatments
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“The great things a man does appear to be great only after they are done.
When they’re at hand, they are normal decisions and are done without knowledge of their greatness”
George S. Patton, Jr., General, USA
