Interface Shear Strength Behavior of Cement-Treated Soil under Consolidated Drained Conditions

This paper presents a series of laboratory tests to determine the shear strength and interface shear strength of cement-treated silty soil under consolidated and drained conditions. The test variables include the effective normal stress, cement content, and curing period. Experimental results indicated that the effective shear strength and interface shear strength of cement-treated soil specimens increased significantly as the cement content increased. After 28 days, the average shear strength ratio increased from 1.28 to 2.4, and the average interface efficiency factor improved from 1.15 to 1.55 as the cement content increased from 3% to 10%. It resulted from an increase in grain size and the fraction of sand-sized particles in the treated soils, approximately in two-time increments for the specimens treated with 10% cement content after 28 days of curing. In addition, the peak and residual values of the shear strength and interface shear strength of the cement-treated soil specimens were determined to assess their brittle behavior under high shear deformation. Last, two new empirical models are introduced herein. The first power equation is to predict the shear strength ratio of cement-treated soil at 28 days of curing using the soil-water/cement content ratio. The other proposed model is useful for assessing the rate of shear strength and interface shear development of cement-treated soil specimens within 56 days of curing.