考虑漏气及井阻非线性的真空预压地基固结解析解

发布时间：2018-03-23 03:40

本文选题：真空预压　切入点：漏气　出处：《岩土力学》2017年09期 　论文类型：期刊论文

【摘要】：基于径向固结理论和等应变假设,考虑真空预压过程中真空泵故障、漏气等不利影响以及排水体井阻时空非线性影响,推导了以排水体中超静孔隙水压uw为函数的3阶拟线性偏微分方程,并将膜下真空度随时间的变化曲线作为边界条件,考虑吹填土的自重固结影响,分别给出了真空预压地基考虑漏气影响且排水体渗透系数随深度线性衰减及时间指数衰减时的固结解析解。最后通过与现有多个固结解的对比分析,认为它们一般为新解的特例,并通过算例计算比较分析,认为井阻随时间影响参数A_2对固结度的影响比随深度影响参数A_1更敏感。当参数A_2足够大时,则认为排水体很快就淤堵以至于不具备排水能力,参数A1则可等效反映真空度随深度的衰减影响,且真空预压过程中漏气对地基固结度具有直接影响,漏气越严重则固结排水越慢,需延长真空预压时间,以保证真空预压效果。
[Abstract]:Based on the theory of radial consolidation and the assumption of equal strain, the vacuum pump failure, air leakage and the space-time nonlinear influence of drainage well resistance are considered in the vacuum preloading process. The third order quasilinear partial differential equation with the function of excess pore water pressure (UW) in drainage water is derived. The curve of vacuum degree under film with time is taken as the boundary condition, and the influence of self-gravity consolidation of blow fill is considered. The consolidation analytical solutions of vacuum preloading foundation considering the influence of air leakage and the linear attenuation of permeability coefficient of drainage body with depth and time exponential attenuation are given respectively. It is considered that they are the special cases of the new solution, and through the comparison and analysis of numerical examples, it is concluded that the influence of well resistance with time on the consolidation degree is more sensitive than that of the parameter A _ 1 with depth. When the parameter A _ s _ 2 is large enough, the effect of the parameter A _ s _ 2 on consolidation degree is more sensitive than that of A _ 1. It is considered that the drainage body is blocked so quickly that it has no drainage capacity, and the parameter A1 can reflect the effect of vacuum attenuation with depth, and the air leakage during vacuum preloading has a direct effect on the consolidation degree of the foundation. The more serious the air leakage, the slower the consolidation and drainage, the longer the vacuum preloading time, to ensure the vacuum preloading effect.
【作者单位】：浙江省水利水电勘测设计院;西北农林科技大学水利与建筑工程学院;
【基金】：浙江省水利水电勘测设计院科标业项目(No.B1608,No.B1609)~~
【分类号】：TU472.33

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