基于水泥搅拌桩的软土路基加固技术

Soft Soil Roadbed Reinforcement Technology Based on Cement Mixing Pile

通过构建不同桩长、桩径、桩间距以及填土高度的水泥搅拌桩模型,进行了详尽的有限元分析,旨在揭示这些因素对软基沉降规律的具体影响,并识别出控制沉降效果的关键因素。主要研究成果如下:(1)软基的沉降量与桩长和桩径之间存在显著的负相关关系,而与桩间距则呈现正相关的趋势,这些关系的线性特征均较为显著。(2)软基沉降量对桩长和桩间距的敏感度较高。结果表明,当桩长每增加2 m时,软基沉降量减少约12%;而桩间距每增大0.5 m,地基沉降量则会显著增大约20%。相比之下,桩径对软基沉降的影响并不显著,其主要影响的是施工过程中的沉降变化。然而,当桩径超过0.8 m后,软基的工后沉降量会出现一个短暂的骤降,随后逐渐趋于稳定。同时,软基的施工沉降量会有显著的增长。综合考虑处理效果与成本效益,建议桩径保持在0.5 m左右较为适宜。(3)水泥搅拌桩桩间距主要影响软基总沉降和工后沉降。仿真过程中不断增加桩间距,路基工后沉降量的增长幅度呈现出增加的趋势。(4)路基填土高度的增加会直接导致地基上部荷载的增大,从而促使软土地基的沉降量相应增加。

This paper conduct a detailed finite element analysis by constructing cement mixing pile models with varying pile lengths,diameters,spacing,and embankment heights.The objective is to reveal the specific impacts of these factors on the settlement patterns of soft foundations and to identify the key factors that control settlement effectiveness.The main findings are as follows:(1)There is a significant negative correlation between the settlement of the soft foundation and both pile length and diameter,while a positive correlation exists with pile spacing,all of which show distinct linear characteristics.(2)The sensitivity of soft foundation settlement to pile length and spacing is high.Specifically,a 2 m increase in pile length decreases the settlement by approximately 12%;conversely,a 0.5 m increase in pile spacing significantly increases the settlement by about 20%.In contrast,pile diameter has a less significant impact on soft foundation settlement,primarily affecting settlement changes during construction.However,when the pile diameter exceeds 0.8 m,a brief sharp decrease in post-construction settlement of the soft foundation occurs,followed by stabilization.The construction settlement of the soft foundation significantly increases.Considering both treatment effectiveness and cost-efficiency,a pile diameter of about 0.5 m is recommended.(3)The spacing of cement mixing piles mainly affects the total and post-construction settlement of the soft foundation.Increasing pile spacing during simulation shows a trend of increased post-construction settlement.(4)An increase in embankment height directly leads to an increase in the upper load on the foundation,thereby causing an increase in the settlement of the soft soil foundation.