应力劳台角对孔隙压力发展的影响

The Effects of Lode’s Angle of stress on Pore Pressure Development

通过中密承德砂在π平面上应力劳台角按不同规律变化的真三轴试验，研究了在不同应力条件下应力劳台角对孔压发展的影响规律。试验研究表明，在较低应力比（不发生剪胀）下，应力劳台角旋转３６０°产生的孔压累积值可达到平均主应力ｐ的１５％～２５％，在较高应力比（出现剪胀）下，应力劳台角旋转３６０°产生的孔压累积值可达到平均主应力ｐ的３０％。不同应力路径也会对孔压有显著影响。

In this paper.effects of Lode’sangle of stress on the pore pressure development under differentstress condition have been studied.A series of true triaxial test on medium sand,under different stressconditions have been conducted. The results indicate that,under low stress ratio and high stress ratio,the accumulated pore pressure caused by Lode’s angle of stress can reach 15%and 30% of mean normalstress respctively. The pore pressure can also be effected remarkably by stress path.