The Mix Design Method And Application Study On Lime-Ash Stabilized Expansive Soil

Because of many merits, such as higher strength, better water stability, and good for environment protection, lime-ash soil is widely used now in high class highway sub-base. But, it is not systematic and comprehensive to study lime-ash stabilized expansive soil. The paper regards the non-side limitation compressive strength at different ages and shrinkage at seventh day as inspection norm, using orthogonal design method, and studies indoors the mix of lime-ash stabilized expansive soil based on the formation mechanism of lime-ash soil's strength and shrinkage and analytical method of mathematical statistics. In the meantime, by indoor compaction experiment of dry and wet methods, the paper studies rolled quality control standard of lime-ash stabilized expansive soil. In addition, combining with construction practice of lime-ash stabilized expansive soil in Nin-Huai expressway, the paper has summarized the key problem of lime-ash soil's quality control.The conclusions are as follows. The first factor to affect lime-ash soil's early strength is lime-ash proportion, and the first factor to affect lime-ash soil's late strength is lime-ash content. So, in mixture's composition design, it should base on later age experimental results. The reasonable lime content in lime-ash stabilized expansive soil is about 8 percent to 12 percent, and the optimal lime-ash proportion is one to three. Lime-ash stabilized expansive soil should take the maximum dry density and the optimum water content from compaction experiment of wet methods as quality control standards. The paper's conclusion will provide some theoretical value and direction for the study and application of lime-ash stabilized expansive soil.