土体强度特性影响因素的试验研究

Experimental study on the effect of soil strength properties

选取不同孔隙比的天然砂土试样进行排列后,对其在不同固结压力下进行常规三轴试验,重点探讨相同试验条件下,排列对砂土抗剪强度的影响。结果表明:排列情况下的砂和混合情况下的砂,试样的偏应力均随围压的增大而增大;相同围压下,排列试样的偏应力峰值明显高于混合试样的偏应力峰值;排列砂样的内摩擦角要大于混合砂样的内摩擦角。同时,利用kf曲线间接获得了排列和混合情况下砂土试样的抗剪强度曲线,并结合试验结果对莫尔-库伦准则进行了修正。

Focusing on the arranged influence on the shear strength of sand under the same test conditions, we select natural and sequenced sands with different void ratio to do the conventional and triaxial tests under different consolidation pressures. Test results shows that deviatoric stress of the sample is increasing with the increase of confining pressure for the arranged sand and the mixed sand, under the same confining pressure, the deviatoric stress peak value of sequenced samples is obviously higher than mixed samples, and internal friction angle of the sequenced samples is higher than mixed sample. Meanwhile, we obtain the shear strength curve of sequenced and mixed sands with the kf curve, and revise the Mohr-coulomb criterion combined with the test results.