Direct shear characteristics of cement stabilized clay subjected to previous shear

The cement stabilization techniques have been applied to various types of infrastructure and become one of the essential techniques. A lot of researches have been conducted on the physical and mechanical properties of the cement stabilized soils, many of which are the studies on the stabilized soil after the hydration. However, the number of researches is limited on the physical and mechanical behavior of cement stabilized soil during the hydration stage and subjected to shear deformation during the hydration stage. In this study, a series of direct shear tests was conducted on the shear behavior of cement stabilized soil to investigate the influence of the magnitude and timing of the shearing on the shear behavior. The researche revealed that the shear strength of the stabilized soil is recovered to the peak strength when it is subjected to the shear deformation prior to the peak strength and the shear strength increases by the cement hydration. On the other hand, when the soil is subjected to the large deformation exceeding to the peak strength, the shear strength loss is not recovered in the following shearing stage. The strength gain due to the cement hydration is also influenced by the initial shearing, where the strength of soil subjected to the large shearing remains small for the curing stage. In this manuscript, the test results are introduced to discuss the influence of the initial shearing as well as the testing procedure.