为研究土石混合体在含超径颗粒情况下的力学响应,利用大型三轴剪切试验仪,分别对体积含石量为25%,35%的非常规土石混合体试样在3种不同围压条件下进行固结不排水剪切试验。试验结果显示:含超径颗粒土石混合体在不排水剪切条件下仍然存在体积变化;含石量35%的土石混合体在围压较高情况下,体应变表现为加载初期剪缩,随后剪胀,二次剪缩,再次剪胀的特征;含石量25%的土石混合体的应力-应变曲线较为平滑,但含石量在35%的情况下,应力-应变曲线则呈现锯齿状特征,且伴随着间接性的应力跳跃现象,相应的体应变、孔隙水压力也出现跳跃现象,且与试样的应力变化具有很好的对应关系。
To investigate the mechanical response of soil rock mixtures(SRM) with the oversized blocks, large-scale triaxial shear consolidated undrained(CU) tests under different confining pressures were conducted on the unconventional sample of soil rock mixtures with the volumetric block proportions(VBP) of 25%, 35% respectively. The results showed that the volumetric change was still observed under the condition of undrained tests for the soil rock mixtures with the oversized blocks. The volumetric strain of soil rock mixtures with the volumetric block proportion of 35% showed the characteristics of shear contraction at the initial stage, the shear dilatation, the secondary shear contraction, and the shear dilatation once again at the higher confining pressures. The curves of the deviator stress against the axial strain are smooth under the volumetric block proportion of 25%. However the curves of the deviator stress against the axial strain have the zigzag shape under the volumetric block proportion of 35%. The jump phenomena of the stress, volumetric strain and pore water pressure were exhibited.