At Razorback Concrete, following ready mix concrete quality testing standards set by the American Society for Testing and Materials (“ASTM”) International ensures a safe and sturdy product.
””The concrete industry relies heavily on following sound quality control measures from start to finish. From the moment water is added to the mix, the chemical reaction begins and starts the clock ticking on how much time is available to complete a job. Everyone involved at Razorback Concrete, from the mixer to the driver to the finishers, plays a vital role in ensuring the pour is a success. From residential to commercial projects, following ready mix concrete quality testing practices ensures the material will cure properly and meet ASTM standards for safety and longevity.
Different Jobs Have Different Standards
The mix for high-stress bridges or buildings is not the same for a backyard patio or sidewalk. The same strength, durability and workability testing that began with the invention of concrete going back to Ancient Rome is still used today for the same reasons. When a batch of mix for a particular project fails to meet testing standards, there can be no allowance for builders fudging results to move a job along. When this happens, necessary steps must be taken to remedy the problem with the mix, which could mean discarding it and starting over. Because of its reliable results and quality ingredients, ready mix concrete is today’s superior product used by many builders and home DIY enthusiasts.
Ready Mix Concrete Quality Testing
There are six critical parameters for quality control testing of ready mix concrete that ASTM standards for building consumer confidence, enhancing safety and improving product quality.
- Sampling – ASTM C172: While the mix is fresh, a representative sample is taken from the center portion of a concrete batch for testing. This is time sensitive and all tests must be completed within 15 minutes of discharge. Care must be taken to protect the sample from elements that could alter the results.
- Slump Test – ASTM C143: Through each phase of a project, the batch consistency must be the same, and within project tolerance requirements. After consolidating a concrete sample inside a conical mold, the amount of slump is measured between the top of the cone and the center of the displaced sample once it is removed. Measured to nearest ¼-inch, too much slump could mean inferior strength or a mix that will not cure.
- Temperature Measurement – ASTM C1064: Obtaining the temperature of the fresh concrete sample is achieved by surrounding the sensing portion of a properly calibrated concrete thermometer by at least three inches of concrete. Ambient temperature must also be recorded as it influences the properties of hardened concrete. This must be completed within five minutes.
- Bulk Density and Yield – ASTM C138: There is some math involved here. Calculating the yield, which is expressed in cubic feet, is determined by dividing the total weight of the batch by the unit weight, or bulk density, which is expressed in pounds per cubic feet. Clue: One cubic yard is equal to 27 cubic feet.
- Pressure Method – ASTM C231: The science of Boyle’s Law, relating pressure to volume, is applied through the use of a pressure-type meter, or air pot, to get a reading of the calibrated hands-free pressure.
- Volumetric Method – ASTM C173: Using a roll-a-meter, this physically demanding test is an accurate measure of the air content of the concrete. Too much air may produce a weak mix depending on the size of the aggregate.
Every project is dependent on ready mix concrete quality testing. At Razorback Concrete, we use the finest materials available to ensure the highest quality mix for the best possible results. See our ready mix quality control standard goals, and use our free online concrete calculator to estimate the amount of our premier ready mixed concrete you will need for your next project.