What does "LA Abrasion" measure in aggregate testing?

In aggregate testing, "LA Abrasion" specifically measures the resistance of aggregate materials to abrasion and impact. This test is important because it simulates the wear and tear that aggregates experience in various applications, particularly in road construction and surface materials. By subjecting aggregates to mechanical actions that mimic service conditions, the LA Abrasion test helps to determine how well an aggregate can withstand the physical forces it will encounter in use, which directly affects the durability and longevity of the finished product.

This understanding of the abrasion resistance is crucial for ensuring that the aggregates used in construction meet the required specifications for strength and performance, thus contributing to the overall quality and safety of the infrastructure. The other options, though relevant to properties of aggregates, do not pertain to the primary focus of the LA Abrasion test, which is centered around physical wear rather than chemical reactions, water absorption, or thermal properties.