非饱和软土路基在长期荷载作用下的一维固结沉降研究

摘要

将Kelvin蠕变模型与Duncan非线性弹性模型串联为非线性粘弹性蠕变模型,来描述非饱和软土路基的本构关系.本构方程结合非饱和土有效应力方程和孔隙水压力与孔隙气压力控制方程,推导出非饱和软土路基在长期荷载作用下的一维固结-蠕变耦合方程,可以求解非饱和土路基任意时间任意位置的孔隙水压力、孔隙气压力.利用求得的孔隙水压力和孔隙气压力通过积分可求得路基的竖向沉降量,并结合工程实例对方程进行了验证.%The constitutive relation of unsaturated soft soil subgrade is described by connecting Kelvin creep model and Duncan nonlinear elastic model in series into nonlinear elastic creep model.The one-dimensional consolidation-creep coupled equation for the unsaturated soft soil subgrade under long-term loads is elicited through the constitutive equation combining with the effective stress equation and pore water pressure and pore air pressure control equation,which can solve the pore water pressure and pore air pressure of the unsaturated soil subgrade at any time and any position,using which,the vertical settlement of the subgrade can be obtained through integration.In addition,the equation is verified combining with the engineering projects.