变幅波浪荷载下饱和南京细砂残余孔隙水压力特性

RESIDUAL PORE WATER PRESSURE PROPERTIES OF NANJING'S SATURATED FINE SAND UNDER WAVE LOADS WITH VARIABLE AMPLITUDES

利用空心圆柱扭剪仪,针对相对密度Dr=50%的饱和南京细砂,进行三向非均等固结状态下的竖向–扭转耦合加载试验,并通过分级加载较为真实地模拟变幅波浪荷载的作用。分别考察初始主应力方向角、初始偏应力比、初始中主应力参数对残余孔隙水压力与累积损失能量关系的影响,结果表明:在相同累积损失能量下,残余孔隙水压力随着初始主应力方向角及初始偏应力比的增大而减小;随着初始中主应力参数的增大而增大。并初步建立残余孔隙水压力与归一化累积损失能量之间的经验公式。

Cyclic triaxial-torsional coupling shear tests are performed on Nanjing＇s saturated fine sand,of which the relative density is 50%,under three-directional anisotropic consolidation state by the hollow cylinder apparatus;and step loading is employed to simulate the effect of wave loads with variable amplitudes more realistically.Influences of initial principal stress direction angle,initial deviator stress ratio and initial intermediate principal stress parameter on the relationship between residual pore water pressure and accumulative lost energy are investigated respectively.The results show that with the same accumulative lost energy,the residual pore water pressure decreases with the increasing of initial principal stress direction angle and initial deviator stress ratio;while it increases with the increasing of initial intermediate principal stress parameter.The empirical formula between residual pore water pressure and normalized accumulative lost energy is established preliminarily.