摘要
为探究初始静偏应力和主应力方向角对珊瑚砂在定向剪切条件下的变形与强度特性的影响,本研究利用GDS空心圆柱扭剪仪,对珊瑚砂和福建砂开展了一系列不同固结条件和大主应力方向角下的不排水定向剪切试验,从有效应力路径、应力-应变关系及强度特性等方面对饱和砂土的力学行为进行了对比分析。结果表明,固结条件与大主应力方向角α_(0)对试样的有效应力路径有显著的影响。相较于等向固结,初始偏转条件下两种砂土试样在剪切初期的剪缩现象均有所减弱,且不同大主应力方向角α_(0)下,相变点后有效应力路径的斜率随偏应力增长呈现明显差异。此外,砂土各应变分量的发展趋势也存在显著差异。在初始偏转条件下,随着大主应力方向角α_(0)的增大,砂土强度呈先降低后升高的趋势,该趋势在珊瑚砂中更为显著,表明其相较于福建砂具有更强的各向异性。
This study investigated the influence of initial deviatoric stress and principal stress direction angle on the deformation and strength characteristics of coral sand during directional shear.A series of undrained directional shear tests were conducted on both coral sand and Fujian sand using a GDS hollow cylinder torsional shear apparatus.These tests involved different consolidation conditions and major principal stress direction angles(α_(0)).The analysis focused on the effective stress path,stress-strain relationship,and strength characteristics of the saturated sands.The test results showed that consolidation conditions andα_(0)significantly affected the effective stress path of the specimens.Under initial anisotropic consolidation,the initial contractive tendency during shear was weaker compared to isotropic consolidation for both sands.Furthermore,after the phase transformation point,the slopes of the effective stress paths exhibited distinct differences with increasing deviatoric stress across differentα_(0)values.The development trends of various strain components also differed significantly.Under initial anisotropic consolidation,the strength of the sands first decreased and then increased asα_(0)increased.This trend was more pronounced in coral sand,indicating that coral sand possesses stronger anisotropy than Fujian sand.
作者
张立雪
刘雷
孙哲
李佩佩
潘坤
ZHANG Lixue;LIU Lei;SUN Zhe;LI Peipei;PAN Kun(Zhejiang Liuding Engineering Construction Co.,Ltd.,Zhoushan 430048,Zhejiang,China;Zhejiang East China Engineering Construction Management Co.,Ltd.,Hangzhou 311113,Zhejiang,China;College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310023,Zhejiang,China)
出处
《地基处理》
2026年第1期33-39,共7页
Journal of Ground Improvement
基金
国家重点研发计划项目(2023YFC3009400)。
关键词
珊瑚砂
初始静偏应力
各向异性
定向剪切
空心圆柱扭剪
主应力方向角
coral sand
initial deviatoric stress
anisotropy
directional shearing
hollow cylinder torsional shear
major principal stress direction angle
