Stabilization of Soil of Hilly Region Using Fly Ash with Various Additives

Abstract

In Civil Engineering construction activities, the soil is stabilized using stabilizers such as stone dust, rice husk ash, fly ash, lime, cockle shell, sisal fiber, coir fiber, cement, etc. In this study, the Well-Graded Silty Sand (SW-SM) soil is stabilized with Fly Ash (FA), Fly Ash with Cement (FAC) combinations, and Fly Ash with Coir Fiber (FACF) combinations. A series of laboratory tests, namely Sieve analysis, Atterberg Limits test, Pycnometer test, Standard Proctor tests, and soaked California Bearing Ratio (CBRs), was conducted on natural soil. The various percentages of Fly Ash (5%, 10%, 15%, and 20%), Cement (2%, 4%, 6%, and 8%), and Coir Fiber (0.5%, 1%, 1.5%, and 2%) by dry weight of soil were used. The CBR test investigated the effectiveness of these additives on soil. The maximum value of CBRs was 25.683% for Soil+10% Fly Ash, 85.376% for Soil+20% Fly Ash+8% Cement, and 18.067% for Soil+5% Fly Ash+0.5% Coir Fiber. The variation of CBRs of soil while treated with FAC combinations reveals that CBRs increase continuously with increments in the percentage of FAC content. The study shows the effective utilization of waste products to stabilize soil.