考虑加载过程的真空联合堆载砂井地基三维固结分析

Three dimensional Consolidation Analysis of Sand Drain’s Ground Under Combined Vacuum and Surcharge Preloading Considering Loading Process

摘要:

在瞬时加载条件下的砂井地基径向和竖向固结的偏微分方程基础上,通过自行编制的程序,将加载过程转化为一系列瞬时加载的组合问题,实现了考虑实际加载过程的真空联合堆载预压下砂井地基的三维固结分析.通过工程算例分析表明,同瞬时加载情况相比,由于受到加载历时的影响,地基的平均固结速度在总体上要小于瞬时加载情况下的地基固结速度.单级或分级加载情况下的地基固结度受加载时间Ti的影响,加载时间Ti越长,地基固结速度越慢.单级加载情况下,在Ti处固结度曲线出现拐点,该点的固结速率最大.

Abstract:

Based on the partial differential equations of both radial and vertical consolidation of sand drain’s ground under instantaneous loading condition,the real loading process is decomposed as a set of instantaneous loading problems by the developed program and threedimensional consolidation analysis is made of the sand drain’s ground under combined vacuum and surcharge preloading with a consideration of the real loading process.The calculation result of the project shows that the average consolidation rate of ground is generally slower than that under instantaneous loading condition due to the effect of loading time.The consolidation degree of ground is influenced by the loading time Ti under the single ramp loading or multiramp loading conditions.The longer loading time Ti is,the slower consolidation rate of ground is.Under single ramp loading,the inflexions of degree of consolidation curves appear at Ti points,the consolidation rate of which is maximum.