无锡地区不同埋深粉质黏土加载流变试验研究

Research of Loading-Rheological Test on WUXI Silty Clay Buried in Different Depth

针对无锡地区③2层、⑥2层粉质黏土,通过设置主应力轴位于水平方向和竖直方向,研究分析不同埋深粉质黏土在不同固结方式、加载方式下的流变特性,并推导了三轴应力状态下的广义Kelvin模型和Burgers模型流变方程,以Burgers模型对试验结果进行了拟合,拟合效果较好.研究分析表明:埋深相同的粉质黏土流变变形速率随偏应力的增加而增大,但当偏应力增加到一定值时流变时间很短,没有流变变形保持阶段;相同类型的土体,埋深较大的流变变形速率、流变阈值较大,流变变形趋于稳定的时间较短;受土体各向异性的影响,流变模型参数随加载方式的不同而不同,但各模型参数均随围压的增加而增大.

Studies on rheological properties of silty clay buried in different depth under different consolidation method and different loading method by setting the principal stress axes in the horizontal and vertical direction were carried out subject to ③2 layer silty clay and ⑥2 layer silty clay in WUXI district,and the rheological equation of generalized Kelvin model and Burgers model under triaxial stress state was derived.The test results fit very well with Burgers model.The test shows that the rheological deformation rate of silty clay buried in the same depth increases with the increase of deviatoric stress,but when the deviatoric stress increases to a certain value,the rheological time is very short and does not maintain the phase of rheological deformation.The rate of rheological deformation and rheological threshold are bigger than that of depth smaller,and the time of rheological deformation to stability is shorter for the same type of soil.By the influence of soil anisotropy,the rheological model parameters vary with the different loading modes,but the model parameters increase with increasing confining pressure.