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 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

schmidt.htm

NDT Penetration 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