ACI Certification Practice Exam

If the sample shears off on one side while checking the slump, what should the technician do?

1. Continue with the test

2. Record the result regardless

3. Disregard the test and retest

4. Adjust the sample and retry

The correct answer is: Disregard the test and retest

When testing for slump, it is crucial to obtain a reliable and accurate measurement of the consistency of the concrete mix. If a sample shears off on one side during the slump test, it indicates that the mix may not be cohesive enough, or that there was an issue with how the slump cone was filled or handled. This shearing affects the validity of the results since the test is designed to measure how much the concrete slumps uniformly. By disregarding the test and retesting, the technician ensures that they are working with a sample that provides a proper representation of the concrete’s properties. This approach also allows for corrections on issues that may have led to the initial failure in the slump test. A retest under controlled conditions should yield results that are more reliable and reflective of the overall quality of the concrete. The other options do not uphold the integrity of the testing process. Continuing with the test could lead to inaccurate data being used for quality control decisions. Recording the result regardless does not acknowledge that the test was compromised and might mislead stakeholders. Adjusting the sample and retrying would not address the fundamental issue of the test’s validity if it was already flawed during the initial attempt.