What is the specified number of strokes required for each layer when rodding the concrete sample?

The specified number of strokes required for each layer when rodding the concrete sample is twenty-five strokes. This established standard ensures that the concrete is thoroughly consolidated within the mold, crucial for achieving accurate measurements of the concrete's workability and consistency. Rodding with this number of strokes helps to eliminate air pockets and guarantees an even distribution of the material within the container, leading to more reliable test results.

The choice of twenty-five strokes is based on industry practices that have been set to standardize testing methods, ensuring uniformity across different testing scenarios. Adhering strictly to this procedure helps maintain the integrity of the sample and, ultimately, the validity of the concrete's properties as evaluated by the test.