横观各向同性土强度与破坏准则的研究

摘要

建立横观各向同性土的破坏准则必须考虑其应力水平和材料横观各向同性的综合影响。本文通过分析横观各向同性土的试验规律,基于横观各向同性土的强度随SMP面（空间滑动面）和沉积面的夹角减小而变小这一假设,建立横观各向同性土的峰值强度表达式。提出了一个关于横观各向同性土的峰值强度和应力张量函数的各向异性变换应力张量。在各向异性变换应力空间,横观各向同性土体被认为是各向同性材料。将变换应力与SMP准Fra则nc结isc合o,海建湾立黏了土横真观三各轴向试同验性数土据的验三证维了破该坏破准坏则准。则分的别合采理用性具。有预横测观结各果向与同试性验的结S果an的ta对M比oni表ca明海,滩本砂文土提和出S的an横观各向同性破坏准则能够合理地描述横观各向同性对土体强度特性的影响。%The combined effects of stress level and material cross-anisotropy should be considered when constructing failure criterion for cross-anisotropic soils. Test results for cross-anisotropic soils were analyzed. Based on the hypothesis that the smaller the angle between the SMP （spatially mobilized plane） and the depositional plane is, the lower the strength. The function of cross-anisotropic peak strength is proposed for cross-anisotropic soils. A transformed stress tensor is proposed as function of cross-anisotropic peak strength and stress tensor. In the transformed stress space, cross-anisotropic soils can be assumed as isotropic material. A three-dimensional cross-anisotropic failure criterion was proposed by combining the transformed stress tensor with the isotropic SMP failure criterion. The criterion is validated through comparisons with experimental data of cross-anisotropic Santa Monica Bench sand and San Francisco Bay Mud. The comparisons demonstrate that the proposed cross-anisotropic failure criterion can reasonably describe the effect of cross-anisotropy on soil strength.