真空联合堆载预压下排水板间距对软基固结效果有限元分析

Finite Element Analysis of Consolidation Effect of Drainage Plate Spacing on Soft Foundation Under Vacuum Combined Surcharge Preloading

本文以广佛江快速通道新会会城至崖门段软基处理工程作为研究对象,着重探究了排水板间距对软基处理效果的影响。根据实际工程条件,采用MIDAS软件建立了使用真空-堆载联合预压法进行软基处理的有限元模型,考虑了0.8 m、1.0 m和1.2 m三种排水板间距对处理效果的影响。计算结果表明:真空联合堆载预压下竖向沉降最大值位于加固区地表中心处,且竖向沉降值随土体向两边的延伸以及深度的增大呈递减趋势。此外,土体的最终沉降量随着排水板间距的增大而减小,且减小速率随着排水板间距的增大而降低。基于计算结果,综合考虑处理成本和固结效果后,本工程采取软基处理时选取的排水板间距为1.0 m。本文所建立的有限元模型能较好地模拟真空-堆载联合预压法对软土地基的固结效果,可为实际工程提供设计指导。

This paper takes the soft foundation treatment project of the Xinhui-Yamen section of Guangfojiang Expressway as the research object and focuses on the influence of drainage slab spacing on soft foundation treatment.According to the actual engineering conditions,the finite element model of soft foundation treatment by the vacuum combined surcharge preloading method was established by MIDAS software.The effects of three kinds of drainage slab spacing(0.8,1.0,and 1.2 m)were investigated.The calculation results show that the maximum value of vertical settlement is located at the center of the ground surface in the reinforced area.And the vertical settlement value tends to decrease with the increment of both distances to the center point and depth.In addition,the final settlement of the soil decreases with the increase of the drainage slab spacing,and the decrease rate decreases with the increase of the drainage slab spacing.The finite element model established in this paper can simulate the consolidation effect of the vacuum combined surcharge preloading method on the soft foundation and provide design guidance for practical projects.