黏土铺盖裂缝淤填固结的理论与试验研究

针对渗透力作用下黏土铺盖裂缝的淤填固结问题,对其固结机理进行阐述。在充分考虑了孔隙比与有效应力、孔隙比与渗透系数的非线性关系条件下,提出了以孔隙比为控制变量的大变形固结微分方程。通过渗透诱发固结试验确定微分方程中的待定系数,该系数综合反映了软黏土初始孔隙比、压缩性、渗透性等随时空变化的影响。采用数值方法求解微分方程,得出了孔隙比在固结过程中随时空的变化规律。采用模型试验模拟了淤填黏土的固结过程并对数值计算结果进行了验证。选择渗漏问题严重的水库进行了现场试验。

Theoretical study and model test on consolidation of warping clay in the cracks of clay blanket

This paper focused on the mechanism of consolidation of warping clay under permeable pressure in the cracks of blanket.Fully considering the non-linear relationships between void ratio and effective stress as well as void ratio and coefficient of permeability,a differential equation with void ratio as a controlting variable was put forward for the large-deformation consolidation.To determine the unknown coefficient(which reflected the variation of initial void ratio,compressibility,permeability.) in the equation,a consolidation test was performed under seepage pressure firstly;and then,numerical method was adopted to solve the equation,so the variation of void ratio during the consolidation was determined.At last,in order to verify the result,both model test(which was designed to simulate the consolidation process of warping clay in the cracks of blanket) and test in-situ(in a reservoir with serious seepage) were carried out.