The Effect of Curing Time on the Engineering Properties of Sawdust and lime stabilized expansive soils

Abstract

Subgrade strength is the main factor in determining the required thickness of any pavement. Therefore, the properties of a pavement subgrade materials must be determined, as they can predict the service life of a pavement. This paper examines the deviation of strength attained by sawdust and lime stabilized expansive soils for subgrade during different curing periods. The methodology used was conducting laboratory tests such as physical properties and mechanical property tests for both treated and untreated soil samples. In the first set-up, the soil was substituted with sawdust in the percentages of 0, 3, 5, and 7% of the dry weight of the soil, and after conducting unconfined compressive strength test, the optimum sawdust percentage obtained was 3%. The 3% sawdust was then mixed with 3% lime and 94% soil for long term tests. The sawdust-lime stabilized samples were cured for 0, 7, 14, and 28 days, and tested for unconfined compressive test and California Bearing Ratio. Based on the analysis of the results, it was concluded that a combination of 3% sawdust and 3% lime significantly improved the California Bearing Ratio and unconfined shear strength, specifically at later curing periods.