Abstract: The artificially cemented soil is widely used to improve the physical and mechanical properties of the natural ground. However, this type of the cemented soil often exhibits a strong nonlinear mechanical behavior while having the high strength and stiffness. This paper takes cementbonded silty clay as an example to systematically analyze the strength and deformation characteristics of samples with different degrees of the cemented structure. The results show that the artificially cemented soil often exhibits significant strain softening characteristics (brittle failure), and its peak strength presents as a statedependent parameter that is significantly affected by the confining pressure and the structure degree, while the residual strength presents as a stateindependent parameter that is less affected by the confining pressure and the structure degree. The compressive stiffness of the cemented soil is significantly higher than that of the remodeled one, and the degradation of cemented structure under the high pressure will cause the isotropic compression line (ICL) to yield and gradually converge to the normal consolidation line (NCL) of the remodeled cemented soil, which provides a way to determine the NCL of the cemented soil. Different from the “shear dilatancy softening” of the over-consolidated clay or the dense sand, the “shear shrinkage softening” phenomenon of the cemented soil often occur due to the degradation of the cemented structure. In addition, the strain localization phenomenon in the cemented soil will affect the overall volumetric change of the sample, resulting in some difference in the critical state lines of artificially cemented soil and corresponding remodeled one.

Key words: Cemented and Structured Soil, Degradation, Peak Strength, Residual Strength, Deformation Characteristic