ACI Concrete Strength Testing Technician Practice Test

Are hand operated machines with a non-continuous loading mechanism permitted?

1. Yes, under certain conditions

2. No, they are not permitted

3. Yes, if they have safety features

4. Only for small-scale tests

The correct answer is: No, they are not permitted

Hand-operated machines with a non-continuous loading mechanism are not permitted for concrete strength testing under standard practices. The reason for this is that non-continuous loading mechanisms can lead to inconsistent and unpredictable force application on the concrete sample, which is crucial for obtaining accurate test results. Continuous loading mechanisms provide a controlled and steady application of load, which is essential to assess the material's properties accurately, such as its compressive strength. Inconsistent loading can introduce variables that compromise the reliability of the results, making it difficult to compare them with established standards or previous test results. Safety features, scale of testing, and specific conditions do not mitigate the fundamental issues related to the use of non-continuous loading mechanisms in strength testing. The preference is always for methods that ensure the integrity and reproducibility of the test results.