路堤荷载下水泥桩复合地基固结特性分析

CONSOLIDATION BEHAVIOR OF SOFT GROUND IMPROVED BY SOIL-CEMENT COLUMN UNDER EMBANKMENT LOADS

水泥桩复合地基在公路和铁路路堤、土石坝、堆场等广泛应用,尤其是路堤荷载下,复合地基的等应变假设不再适用,因此需要对其固结沉降特性进一步开展研究。文中采用有限元模拟分析,研究路堤荷载下水泥桩复合地基的固结性状,并分析了多个因素的影响。研究表明,桩长对复合地基固结特性影响很大,随着桩长增加,复合地基沉降明显减小,固结速度加快。增大桩身模量和桩体渗透系数都可以加快复合地基固结;同时,桩间距增大,地基固结速度减慢。从控制沉降角度,增加桩长是较为有效的措施。研究为路堤荷载下水泥桩复合地基设计提供了参考。

Soil-cement column is widely used in highway and railway embankments,earth-rock dams,and stock⁃yards.Especially under embankment load,the equal strain assumption of composite foundations no longer applies well.Further research on consolidation settlement characteristics is urgently needed.This paper utilizes finite ele⁃ment simulation to study the consolidation behavior of cement pile composite foundation under embankment load,and analyzes the influence of multiple factors.It is found that pile length has a great influence on the consolidation characteristics of composite foundations.As pile length increases,the settlement of composite foundations signifi⁃cantly decreases and the consolidation speed accelerates.Increasing the pile modulus and pile permeability coeffi⁃cient promotes the consolidation of the composite foundation.At the same time,as the pile spacing increases,the foundation consolidation speed slows down.In order to control the settlement,increasing pile length is an effective measure.This study may provide the reference for the design of soft ground improved by soil-cement column under embankment load.