应力路径对超固结土峰值强度特性的影响分析

超固结土的峰值强度不仅与超固结度有关,也受到应力路径的影响。基于统一硬化模型(UH模型)和广义非线性强度准则,对超固结土的峰值强度特性进行分析,预测超固结土在常规三轴压缩、等p路径、不排水路径下的峰值强度,得到其峰值强度大小关系。利用广义非线性强度准则描述三种路径下的超固结土峰值强度的非线性,并确定其表达式。通过与试验结果对比表明所建议分析方法的有效性。

ANALYSIS OF EFFECT OF STRESS PATHS ON PEAK STRENGTH CHARACTERISTICS OF OVER-CONSOLIDATED CLAY

The peak strength of over-consolidated clay is not only related to the degree of consolidation,it is also impacted by stress paths. The method based on the unified hardening model( UH model) and the generalized nonlinear strength criterion was analyzed the peak strength of over-consolidated clay and offered the theory basis for the over-consolidated clay under complex stress paths. By describing the peak strength of over-consolidated clay under the triaxial compression,constant principal stress,and undrainage consolidation stress path,the relationship of their peak strength could get by UH model. Generalized nonlinear strength criterion was used to describe the non-linear degree of the three paths and to determine the expression equation. The comparation with the test results showed that the proposed analysis method was effective.