Why surcharge weight cbr test?

The surcharge weight in a California Bearing Ratio (CBR) test is used to simulate the pressure that would be applied by overlying materials, such as pavement or soil layers, in real-world conditions. By applying this surcharge, the test more accurately reflects the strength and load-bearing capacity of the subgrade material under typical service conditions. This ensures that the results of the CBR test provide a reliable assessment for designing roadways and other structures.