ACI Concrete Strength Testing Technician Practice Test

Before reaching what percentage of the anticipated specimen strength, should the vertical alignment of the cylinder be checked?

1. 5%

2. 10%

3. 15%

4. 20%

The correct answer is: 10%

Checking the vertical alignment of the concrete cylinder should be done before it reaches 10% of its anticipated strength. This is crucial because proper alignment of the specimen during testing directly influences the accuracy and reliability of the compressive strength results. If the cylinder is misaligned, it can lead to uneven load distribution and inaccurate measurements, which may compromise the integrity of the test. The 10% threshold serves as a proactive measure to ensure that the specimen is being evaluated under optimal conditions. At this early stage of strength development, any misalignment can often be corrected more easily, leading to better overall test outcomes. Maintaining this diligence early on prevents potential issues that could affect the testing process later as the specimen continues to cure and gain strength.