Effect of Soil-Fly Ash Mix on the Stability of Pavement Subgrade

Abstract

The overall performance of pavement is very much responsive to the characteristics of the soil subgrade. For that reason, weak subgrades are augumented by adopting the most efficient and profitable stabilization techniques. The subgrade soil stabilization is one of the principal and major processes in the construction of any highway. The whole aim of this thesis is to investigate the effect on the stability of pavement subgrade by the application of soil-fly ash mix. In this regard a laboratory experimental program was considered to study the effect caused by the action of fly ash stabilization on the geotechnical trademarks of expansive subgrade soils. Expansive soil treated with different percentages of fly ash i:e 10, 20, 30, and 40 percent were taken into account. For analysis of stabilization of soil using fly ash, CBR, Compaction, specific gravity, sieve analysis, water absorption tests are performed. Properties used for investigating are Liquid Limit, Plastic Limit, Optimum Moisture Content and California Bearing Ratio. The experimental data reveals that addition of fly ash admixture to the soil has a great influence on its properties. Fly ash has been used successfully in many projects to improve the strength characteristics of soils. Fly ash can be used to stabilize bases or subgrades, to stabilize backfill to reduce lateral earth pressures and to stabilize embankments to improve slope stability.