In flexible pavements, different structural layers are provided to safely distribute and withstand traffic loads. The California Bearing Ratio (CBR) value is used to determine the required thickness of these layers, especially for subgrade and base course materials.
For lower CBR values, greater pavement thickness is required. Conversely, higher CBR values allow thinner pavement sections.
If the CBR value of a material is very low, the required layer thickness becomes excessively high, which makes the design uneconomical. Therefore, CBR plays a crucial role in the cost-effective design of flexible pavements.
