定向剪切应力路径下重塑黄土应力—含水率—应变关系试验研究

Experimental study on stress-water content-strain relationship of remolded loess under directional shear stress path

为了研究定向剪切应力路径下,重塑黄土的强度和应力—含水率—应变关系,采用浙江大学空心圆柱扭剪仪,针对6种不同初始含水率制备的重塑黄土,在中主应力系数和平均主应力恒定条件下,进行定向剪切试验,重点研究初始含水率对重塑黄土定向剪切特性的影响。结果表明:在相同的初始主应力方向角下,含水率越高的试样,其破坏剪应力对应的剪应变值越小;含水率超过17%重塑黄土强度会骤减。经过分析,充分说明了含水率对重塑黄土强度的影响具有区间效应,为西宁地区黄土工程施工提供了理论指导。

In order to study the relationships between strength and stress-water content-strain of remolded loess under directional shear stress path,the strength and deformation tests were conducted with hollow cylinder apparatus in Zhejiang University.6 kinds of remolded loess with different initial moisture content were used to carry out directional shear test under constant principal stress coefficient and mean principal stress.The influence of initial moisture content of remolded loess on directional shear properties was discussed.The results show that under the same initial principal stress direction,the fracture shear stress of the sample with the higher water content corresponds to the smaller initial shear strain.The strength of remolded loess will plummet when its moisture content is more than 17%.The comparative analysis reveal that the impact of water content on the strength of remolded loess has a range effect.The results of this study can provide theoretical guidance for loess construction in Xining area.