The ______________________ test is done to concrete to ensure that when it sets it will have proper strength needed.

The slump test is specifically designed to measure the workability and consistency of freshly mixed concrete, rather than its strength. It helps to assess the concrete's fluidity and ability to be molded, which are crucial factors for proper placement and compaction. However, the strength of concrete is typically evaluated using the compression test, as it specifically measures the ability of concrete to withstand axial loads without failure when it sets.

In practical applications, the compression test involves applying force to a concrete sample until it fails, allowing for the calculation of its compressive strength, which is a key characteristic for structural elements. The other test types mentioned, like tensile and flexural tests, further evaluate different aspects of concrete under varying stresses, but they do not directly measure the strength of the concrete as it sets in the same way the compression test does.