ACI Certification Practice Exam

The method that determines the slump of concrete is the Slump Cone Test. This test is specifically designed to measure the consistency or workability of fresh concrete. The process involves filling a conical mold (the slump cone) with concrete, removing the cone, and measuring how much the concrete slumps or settles. The amount of subsidence indicates the workability; a higher slump means more fluid concrete, while a lower slump suggests a stiffer mix.

The other options, while important tests in concrete evaluation, serve different purposes. The Vebe Test measures the workability of concrete but does so through a different process involving vibration. The Compression Test evaluates the strength of hardened concrete by applying pressure until failure, while the Flexural Test assesses the resistance of concrete against bending forces, focusing on tensile strength characteristics. These methods do not provide a direct measurement of the slump, which is unique to the Slump Cone Test.