control tests for concrete

7/29/2019 Control Tests for Concrete

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Control Tests for Concrete

Ch. 16


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Project Specifications Characteristics of the mixture

Maximum size aggregate

Minimum cement content Characteristics of the cement, water

aggregates and admixtures

Characteristics of the plastic and/or hardened

concrete Temperature, slump, air content

Compressive and/or flexural strength


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Frequency of Testing FA Aggregate Moisture testing

Twice daily

1% change effects mix water requirement by 13pcy

Slump Test

First batch of concrete delivered each day

When consistency appears to vary

Strength cylinders are made

Temperature of concrete recorded


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ContAir content tests

Initial batch of concrete

When concrete test cylinders are made

Temperature of concrete recorded


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Cont Concrete strength testing for each class of

concrete placed

Not less than once per day Not less than once for each 150 cy of concrete

placed

Not less than once for each 5000 sq ft. of surfacearea for slabs and walls.

One 7-day, two 28-day cylinders are requiredfor each test and one or more holdspecimens.


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Moisture Content of

Aggregates Oven dry method

Microwave

Moisture meter

Electrical resistivity


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Plastic Concrete Sampling freshly mixed concrete

ASTM C 172

2 or more portions within a 15 minute window Consistency

Slump test ASTM C 143 Test to be completed in 2 minutes after obtaining

sample

K-slump tester

Kelly Ball

Vebe consistometer


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Cont Temperature measurement

ASTM C 1064

This test should be completed within 5 minutesafter obtaining the sample

Air content

ASTM C 231 pressure method

ASTM C 173 volumetric method

Test to be started within 5 minutes after obtainingsample


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Density and YieldASTM C 138

Unit weight of plastic concrete

Yield provides information concerningvolumetric quantity of concrete producedper batch

Y = total weight of components/unit weight


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Time of settingASTM C 403

Penetration resistance as a function of time

Initial set 500 psi (2-6 hours)

Final set 4000 psi (4-12 hours)


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Strength specimens ASTM C 31field molded specimens

ASTM C 192 laboratory specimens

6 x 12 for 1 inch or greater max size CA 4 x 8 for -inch or less

Beams are 6 x 6 x 30-inches

Field specimens cured in same manner asstructure

Lab specimens cured in sat. limewater ormoist room.


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Destructive Testing of

Hardened Concrete ASTM C 39 for test cylinders

Strength effected by L/D ratio

Condition of the ends of samples

Sulfur mortar caps vs unbonded neoprene caps Loading rate (20-50 psi/sec)

ASTM C-78 for flexural strength using third pointloading.

ASTM C-293 for flexural strength using center pointloading.


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Strength Tests of Hardened

Concrete Compressive Strength Testing of Concrete,

ASTM C39

Unbonded neoprene caps, ASTM C1231 Flexural Strength - 3rd Point Method, ASTM

C78

Flexural Strength - Center Point Loading,ASTM C293

Splitting Tensile Strength of Concrete. ASTMC496

fr = 7.5*(fc)1/2


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Failure Modes of Compression

Testing


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Flexure Strength Testing -

Third Point Loading


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Flexure Strength Testing -Center Point Loading

P

L = span

depth


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Splitting Tensile Test


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Air Content

Petrographic Determination ofAir-VoidSystem, ASTM C457

hardened concrete air-void system

void size and air-void distribution system

freeze/thaw durability


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Density(Gs), Absorption andVoids

ASTM C642

Density or Unit Weight of HardenedConcrete

Absorption of Hardened Concrete

Volume of Voids in Hardened Concrete

Density of Hardened Concrete byNuclear Density Gage


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Other Tests

Determination of Chloride Ion Contentin Hardened Concrete ASTM C1152

ASTM C1218

Volume and Length Change

Shrinkage of Hardened ConcreteASTM C157


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Durability Frost Resistance

ASTM C666

Freezing in air and thawing in water

Freezing in water and thawing in water Dynamic modulus of elasticity

Sulfate Resistance

ASTM C1012

Corrosion Resistance

ASTM C876 - Potentiometric Mapping


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Corrosion Determination -Potentiometric Mapping


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Cont

Abrasion Resistance

ASTM C779

ASTM C944 ASTM C1138 (underwater test)

Carbonation

Phenolphthalein indicator method

Permeability

ASTM C1202 Rapid Chloride Permeability Test


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Nondestructive Test Methods

Rebound Hammer Tests

Schmidt Hammer


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http://www.corvib.com/concrete/schmidt.htm
http://www.worldoftest.com/images/ndt/WM250.jpg


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NDT

Penetration Testing- Windsor Probe

Maturity Testing In-place Compressive Strength

Pullout Tests

In-place Shear Strength


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NDT

Ultrasonic Pulse Velocity

Dynamic modulus of elasticity

Cracking


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Pulse Velocity Testing


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NDT

Other Dynamic Tests

Impact echo


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Impact Echo Testing

control tests for concrete

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