What must be done if the concrete contains aggregate larger than permitted for a particular test method?

The appropriate action when dealing with concrete that contains aggregate larger than what is permitted for a specific test method is to wet-sieve the sample before testing. This process involves passing the concrete sample through a sieve while it is wet, allowing the larger aggregates to be separated from the smaller particles.

Wet-sieving is crucial because many test methods have strict size requirements for aggregates to ensure accurate results. By removing the excess large aggregates, you maintain the integrity of the test and ensure that the sample used is representative of what the test method is designed to evaluate. It preserves the reliability of measurement by adhering to the standardized conditions specified for the testing procedure.

Choosing to ignore the large aggregates compromises the test's accuracy and would likely yield invalid results. Simply using smaller aggregates directly would not reflect the original composition of the concrete mix and could lead to incorrect conclusions about its properties. Altering the test method is not recommended unless it is validated for the specific characteristics of the concrete sample in question. Thus, wet-sieving is the most appropriate and accepted practice in this scenario.