Improvement in CBR Value for Flexible Pavement Design Using Solid Waste:A Case Study

California Bearing Ratio (CBR) value is an important soil parameter for design of flexible pavements as per IRC recommendation. In this study, attempts have been made to improve the soil strength by the addition of various proportions of fly ash (FA) & rice husk ash (RHA) and correlate the CBR values for the flexible pavement design. A series of proctor tests and CBR tests (soaked for 96 hours) were conducted by adding different proportions of FA & RHA of soil samples collected from different places of Durgapur, India & its nearby areas and optimized proportion is arrived. As soils of different area are having different strength properties, different optimum values of FA & RHA can be obtained for different region. Developed stabilized soil mixtures showed satisfactory increase in CBR values up to a specific amount of addition of FA as well as RHA and can be used for construction of embankments and stabilization of sub-grade soil. The use of locally available soils, FA and RHA in the production of stabilized soils for such applications can provide sustainability for the local construction industry.