Which test is used to determine the crushing resistance of aggregate?

The Los Angeles abrasion test is specifically designed to evaluate the toughness and resistance to wear of aggregates used in construction. This test measures the aggregate's ability to withstand mechanical degradation under specified conditions, simulating conditions that material would experience in service. The test involves subjecting aggregate samples to a specified number of revolutions in a rotating drum with steel spheres, which effectively mimics the grinding and crushing effects that aggregates might encounter in real-world applications.

The outcome of this test indicates how well the aggregate can withstand crushing and degradation during use in concrete and road constructions, making it a vital factor for evaluating the durability and quality of aggregates. This makes it the most relevant test for determining crushing resistance.

Other tests mentioned are focused on different properties. For instance, the California bearing ratio test assesses the strength of subgrade soil or base aggregates for road construction, whereas the unconfined compressive strength test measures the load-bearing capacity of soil or rock samples without confining pressures. The Atterberg limits test evaluates the plasticity of fine-grained soils but does not relate to the resistance to crushing of aggregate materials.