Which of the following tests is used to assess the suitability of aggregates for pavements?

The California Bearing Ratio (CBR) test is widely recognized as a standard method for evaluating the strength and suitability of subgrade and base materials, specifically aggregates, for pavement applications. The CBR test measures the strength of the material by comparing its resistance to penetration under specified conditions to that of a standard crushed rock material. The result provides an index value that can be directly related to the performance of the material in a pavement structure.

The CBR test is particularly important in determining how well aggregates can support loads and how they will behave under traffic conditions, making it essential for engineers to assess whether the aggregate is appropriate for use in road construction and design. The index value derived from the CBR test helps in the design of pavement thickness and is a key factor in ensuring long-term pavement stability and performance.

In contrast, while the Plasticity Index test evaluates the plasticity characteristics of aggregates, and the Moisture-Density Relationship test (often conducted through Proctor testing) assesses the compaction characteristics of soils and aggregates, neither directly informs on the suitability for pavements. The Granular Base test assesses the properties of granular materials but does not specifically focus on their strength in pavement applications as the CBR test does.