真空预压下土体强度增长机理及其计算方法研究

Study on Mechanism and Calculation of Shear Strength of Soil Body Consolidated by Vacuum Preloading

在真空预压法加固过程中,土体产生等向固结压力。简单地将真空预压等同堆载作用的处理方法不尽合理,将导致计算土体抗剪强度时出现较大偏差而不宜忽视。该文采用摩尔应力圆来阐述土体受等向固结应力和K0固结应力的不同特点,从而导出二者土体抗剪强度增长偏差的解析解。实例分析表明,该方法较常规方法更准确可行。

In the preceeding of vacuum preloading, soil is consolidated by isotropic consolidation pressure, which is different from consolidation pressure K0 in superload preloading. The method of vacuum preloading pressure being treated simply as overburden consolidation pressure is not suitable. Their differences are expounded by Mohr stress circle in the paper and the formula of the differences can be deduced. The results of the example show that this method is more precise than common method.