真空预压地基承载力研究

Research on bearing capacity of vacuum preloaded subsoil

在确定软土地基经真空预压处理后地基的承载力过程中,把真空度以球形压作用在软土地基中,而在求土体的自重应力时,考虑K0≠1,得到地基土中某一点的应力状态,根据莫尔—库伦破坏准则,利用MATLAB语言编制程序来求解地基承载力。该方法弥补了众多现场试验方法求取承载力的局限性,改正了推导真空预压处理后地基承载力公式过程中的一些缺陷。参数分析表明,固结度越高,土体承载力呈线性增长,且同一固结度下,增大相同的ΔK0,承载力随之增大,且增幅随着K0的增大而越来越大;地基土的承载力随K0的增加呈线性增长,且同一K0下,增加相同量的固结度,承载力的增长率大致相等;土体的黏聚力与承载力近似呈线性关系,摩擦角与承载力近似呈指数关系。

In order to find bearing capacity of subsoil witch has been preloaded by vacuum,determining vacuum degree as spherical pressure stress acting on subsoil,and cancelled the assumption K0=1 when finding geostatic stress of subsoil.According these,using MATLAB program to find the numerical answer of subsoil bearing capacity based on mohr-coulomb criterion.This method makes up limitations which generated by in-situ tests processing,and corrects some calculating mistakes when proposes calculation formulas of subsoil bearing capacity which obtained K0≠1 by some scholars.Parameters analysis shows that the bearing capacity of vacuum preloaded subsoil is increasing when degree of consolidation increases.And the bearing capacity increases when increasing a same value of ΔK0 in a certain degree of consolidation.The bearing capacity is linear growth with increasing of K0.And the growth rate of bearing capacity approximately the same with a same increment of degree of consolidation in a certainK0.Cohesion and bearing capacity have a relationship of approximate linear.Friction angle and bearing capacity have an exponential relationship.