黄土侧向变形的真三轴试验研究

保持小主应力、中主应力不变,在大主应力方向加荷是实际工程中存在的一种应力路径,就该应力路径分别对不同含水率的重塑黄土进行了几组真三轴试验,对其应力-应变关系及反映侧向变形变化规律的泊松比进行了特定条件下的研究.研究结果表明,应力-应变关系的偏差应力和初始切线模量随含水率的增大而减小,相同的偏差应力下含水率越大侧向应变就越大.在上述应力路径下剪切,中主应力方向首先压缩,但表现不明显,很快就转为膨胀,小主应力方向膨胀,泊松比可以大于0.5,且小主应力方向膨胀量大于中主应力膨胀量.

Deformation Characteristics of Loess by True Triaxial Test

Keeping minor principle stress and medium principle stress fixed and loading in the direction of maximum principle stress are the potential stress path in practical projects,under which several groups with different water contents of true triaxial tests about remolding loess are studied. Results show that the values of initial elastic modulus and principal deviator stress decrease with water content increasing. In certain defined principal deviator stress,lateral deformation increases with water content increasing. The Poisson's ratio can be greater than 0.5 in the direction of minor principle stress and the expansion in the direction of minor principle stress is greater than that in the direction of medium principle stress.