Characterization of Field Compacted Soils (Unsoaked) Using the California Bearing Ratio (CBR) Test

Abstract

In the past decades researchers have developed many correlations to predict the soil behavior using non-destructive methods including the California Bearing Ratio (CBR) test. The CBR correlation with resilient modulus is still used in the design of compacted soil sub grade in supporting pavements. It has been demonstrated that field compacted soil properties are greatly influenced by the compacter used. The correlations in the literature are very much limited to laboratory compacted soils. CBR is very much affected by the type of soil and the method of compaction. Hence it is important to develop correlation for field compacted samples. In this study, over 20 field compacted samples of 2 different types of soils (CL and SC) were tested and analyzed. The liquid limits for the soils were in the range of 22 % to 44 %. Optimum dry densities for the field compacted soils varied from 15 to 21 kN/m3. The upper limit for the CBR, undrained shear strength and modulus for the field compacted soils were 70%, 800 kPa and 6 MPa, respectively. The correlations were developed and compared to the information in the literature. Finite element method was used to model the CBR test.