What is the objective of the California test method?

The objective of the California test method, specifically applied in the realm of civil engineering, is to establish the physical properties and performance characteristics of aggregates. This method evaluates how aggregates will react under various conditions, ensuring they meet specifications for use in construction projects. It assesses factors such as gradation, moisture content, and compaction, which are critical for materials used in pavement construction and other applications. By determining these characteristics, engineers can ensure that the aggregates will perform efficiently and safely, contributing to the structural integrity of the projects they are used in.

The other options focus on specific soil properties or types of testing that are not the primary aim of the California test method. Measuring water retention, organic content, or shear strength pertains to different testing methodologies and objectives that address particular aspects of soil behavior rather than the broader characterization of aggregates.