Control Tests for Concrete Ch. 16. Project Specifications Characteristics of the mixture Maximum...
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Transcript of Control Tests for Concrete Ch. 16. Project Specifications Characteristics of the mixture Maximum...
Control Tests for Concrete
Ch. 16
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
Frequency of Testing FA Aggregate Moisture testing
Twice daily 1% change effects mix water requirement
by 13 pcy Slump Test
First batch of concrete delivered each day When consistency appears to vary Strength cylinders are made Temperature of concrete recorded
Con’t Air content tests
Initial batch of concrete When concrete test cylinders are
made Temperature of concrete recorded
Con’t 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
surface area for slabs and walls. One 7-day, two 28-day cylinders are
required for each test and one or more “hold” specimens.
Moisture Content of Aggregates Oven dry method Microwave Moisture meter
Electrical resistivity
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 ½ minutes after obtaining sample
K-slump tester Kelly Ball Vebe consistometer
Con’t Temperature measurement
ASTM – C 1064 This test should be completed within 5
minutes after obtaining the sample Air content
ASTM C 231 – pressure method ASTM C 173 – volumetric method Test to be started within 5 minutes after
obtaining sample
Density and Yield ASTM C 138
Unit weight of plastic concrete Yield provides information concerning
volumetric quantity of concrete produced per batch
Y = total weight of components/unit weight
Time of setting ASTM C 403
Penetration resistance as a function of time
Initial set 500 psi (2-6 hours) Final set 4000 psi (4-12 hours)
Strength specimens ASTM C 31 –field molded specimens ASTM C 192 – laboratory specimens 6 x 12 for 1 inch or greater max size CA 4 x 8 for ¾-inch or less Beams are 6 x 6 x 30-inches Field specimens cured in same manner
as structure Lab specimens cured in sat. limewater
or moist room.
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 point loading.
ASTM C-293 for flexural strength using center point loading.
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. ASTM C496
fr = 7.5*(f’c)1/2
Failure Modes of Compression Testing
Flexure Strength Testing - Third Point Loading
Flexure Strength Testing - Center Point Loading
P
L = span
depth
Splitting Tensile Test
Air Content Petrographic Determination ofAir-
Void System, ASTM C457 hardened concrete air-void system void size and air-void distribution
system freeze/thaw durability
Density(Gs), Absorption and Voids
ASTM C642 Density or Unit Weight of Hardened
Concrete Absorption of Hardened Concrete Volume of Voids in Hardened
Concrete Density of Hardened Concrete by
Nuclear Density Gage
Other Tests Determination of Chloride Ion
Content in Hardened Concrete ASTM C1152 ASTM C1218
Volume and Length Change Shrinkage of Hardened Concrete
ASTM C157
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
Corrosion Determination - Potentiometric Mapping
Con’t Abrasion Resistance
ASTM C779 ASTM C944 ASTM C1138 (underwater test)
Carbonation Phenolphthalein indicator method
Permeability ASTM C1202 “Rapid Chloride Permeability
Test
Nondestructive Test Methods
Rebound Hammer Tests Schmidt Hammer
http://www.corvib.com/concrete/schmidt.htm
NDTPenetration Testing
- Windsor Probe Maturity Testing
In-place Compressive Strength Pullout Tests
In-place Shear Strength
NDT Ultrasonic Pulse Velocity
Dynamic modulus of elasticity Cracking
Pulse Velocity Testing
NDT Other Dynamic Tests
Impact echo
Impact Echo Testing