人民长江2025，Vol.56Issue(6)：176-181,6.DOI:10.16232/j.cnki.1001-4179.2025.06.023
定轴剪切下非等向固结软土不排水力学特性研究
Undrained behavior of anisotropically consolidated soft clay under shearing of fixed principal stress axes condition
摘要
Abstract
In order to study undrained mechanical properties of anisotropically consolidated soft clay under initial deviation of principal stress axes,a series of undrained shear tests were conducted on the anisotropically consolidated soft clay using the GDS hollow cylinder apparatus to investigate the influence of different principal stress axes directions on deformation,strength,and non-coaxiality behavior.The test results indicate that the strain development,stress path and pore pressure development are all de-pendent on the principal stress orientation,and there are three patterns of deformation,namely vertical compression,shear deform-ation and radial extrusion,respectively.Compared with the isotropic consolidation case,the undrained shear strength of the aniso-tropically consolidated sample is enhanced,showing an approximate semi-elliptic strength envelope surface in the τzθ-(σz-σθ)/2 plane,which demonstrates significant strength anisotropy.The soil strength tends to decrease and then increase as the angle of the major principal stress axis α0 increases from 0° to 90°,and it reaches the maximum and minimum value at α0=0° and 45 °,respectively.Furthermore,the non-coaxial angle decreases gradually during undrained shearing,the samples show a near ze-ro non-coaxial angle when samples are subjected to pure compression,pure twist-shear and side extrusion.The non-coaxial phenomenon manifests obviously when the soil samples are in compressed twist-shear and extruded twist-shear.关键词
软土/主应力方向/不排水力学特性/抗剪强度/非共轴/定轴剪切试验Key words
soft clay/principal stress orientation/undrained strength/non-coaxiality/fixed principal stress axes shearing分类
建筑与水利引用本文复制引用
孙枫,谢杰杰,许莹莹,施周桓,潘坤..定轴剪切下非等向固结软土不排水力学特性研究[J].人民长江,2025,56(6):176-181,6.基金项目
国家重点研发计划项目(2023YFC3009400) （2023YFC3009400）
