Study on Strength and Deformation Characteristics of Expansive Soils Treated with Lime-biomass Ash

Abstract

This paper investigates the strength deformation of the lime-biomass ash treated expansive soils. The unconfined compressive strength, one-dimensional compression of the modified expansive soil of compaction were studied. The results showed that the maximum dry density and optimum moisture content of expansive soil decreased with the increase of lime and biomass ash content; The unconfined compressive strength test results show that there is no remarkable change in the unconfined compressive strength of the soils immediately treated with biomass ash, but the sample after 7 days of curing period of strength has been greatly improved, especially after the addition of lime is more obvious; the compression coefficient, the rebound coefficient of the saturated expansive soil with lime-biomass ash is significantly smaller than saturated expansive soil. The compressive modulus of the modified expansive soil increases with the increase of vertical pressure, which reflects the hardness of the improved expansive soil.