地铁荷载下软黏土微结构与宏观变形的相关性

Correlatability of Microstructure Change and Macroscopical Deformation of Soft Clay Under Subway Load

摘要:

针对地铁荷载下饱和软黏土的宏观变形，从微观试验出发，采取定量化的试验手段，以上海地区地铁行车荷载作用下的饱和软黏土为研究对象，将其宏观变形与各微观结构参数进行相关性分析.从振动前后各微观结构特征参数的变化出发，辅以电镜扫描分析，揭示了地铁行车荷载下隧道周围土体产生宏观变形的机理及发展趋势.为预测软土地区地铁运营引起的地基沉降提供了有益的参考.

关键词:地铁荷载; 压汞试验; 饱和软黏土; 宏观变形

Abstract:

In order to explain macroscopical deformation of saturated soft clay under subway load,the cyclic triaxial test,mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) are conducted and the correlatability between microstructure change and macroscopical deformation of saturated soft is analyzed.The mechanism and tendency of macroscopical deformation of saturated soft clay around tunnel under subway load are obtained,providing basis for predicting the subgrade subsidence due to subway load.

Key words:subway load; mercury intrusion porosimetry (MIP); saturated soft clay; macroscopical deformation