ACI Concrete Strength Testing Technician Practice Test

What is the implication of a cylinder having more than 2% difference in diameter?

1. It can be tested

2. It needs to be replaced

3. It is not acceptable for testing

4. It requires further evaluation

The correct answer is: It is not acceptable for testing

A cylinder with more than a 2% difference in diameter is considered not acceptable for testing due to the potential for inconsistent results and flawed compression strength measurements. Standard specifications for concrete testing, such as those outlined by the ACI (American Concrete Institute), emphasize the importance of using uniform and properly sized specimens during strength testing. When a cylinder is outside the acceptable dimensions, it may not distribute stress uniformly when subjected to compressive forces, which can lead to erroneous results. The failure patterns could also be influenced by the irregularity, which may not reflect the true strength of the concrete mixture. Therefore, testing such a cylinder could compromise the reliability of the data obtained, which is crucial for assessing the quality and performance of the concrete. In the context of quality control and assurance, maintaining strict adherence to dimensional tolerances ensures that all tested materials provide valid comparisons and insights into the expected performance of concrete in actual field conditions.