What is the maximum size aggregate permitted for the slump test?

The maximum size aggregate permitted for the slump test is 1 ½ inches. This specification ensures that the test results accurately reflect the workability and consistency of the concrete mix. Larger aggregate sizes could interfere with the flow and stability of the concrete when it is being tested, leading to inconsistent results. A uniform maximum aggregate size helps maintain the integrity of the test process by ensuring that the aggregates do not restrict the movement of the concrete during the test, which could skew the data about the mix's workability. Keeping the maximum size at 1 ½ inches allows for a reliable assessment of the concrete's properties relevant to construction and its intended use.