What type of concrete test is performed when assessing the flexural strength of beams?

The assessment of flexural strength in concrete beams specifically requires a flexural strength test, which is defined in standards such as ASTM C78. This test method determines the concrete's ability to resist bending and is crucial for applications where tensile stresses are a concern, such as in beams subjected to bending moments in structural elements.

During the test, a beam sample is subjected to a load until failure occurs, allowing for the calculation of the flexural strength based on the maximum load carried by the beam at the moment of failure. The results are indicative of how the concrete will perform under real-world conditions, particularly in structural applications where flexural stress is significant.

In this context, the other types of tests mentioned do not measure flexural strength but rather other characteristics of concrete. Compressive strength tests gauge the material's ability to withstand axial loads, split tensile strength tests measure the tensile strength indirectly, and shrinkage tests evaluate changes in volume over time. Each serves a different purpose and is critical in developing a complete understanding of concrete behavior but does not specifically assess flexural strength.