柱状和格栅状搅拌桩联合加固河堤变形特征离心模型试验研究  

Centrifugal model tests on deformation characteristics of river embankment improved by combined columnar and grid-form columns

作　　者：沈晨 章定文[1,2,3] 宋涛 张国龙 SHEN Chen;ZHANG Dingwen;SONG Tao;ZHANG Guolong(School of Transportation,Southeast University,Nanjing 211189,China;Key Laboratory of Transport Industry of Comprehensive Transportation Theory(Nanjing Modern Multimodal Transportation Laboratory),Ministry of Transport,PRC,Nanjing 211100,China;Jiangsu Key Laboratory of Low Carbon and Sustainable Geotechnical Engineering,Nanjing 211189,China;Anhui Survey&Design Institute of Water Resources&Hydropower Co.,LTD,Hefei 230088,China)

机构地区：[1]东南大学交通学院,江苏南京211189 [2]综合交通运输理论交通运输行业重点实验室(南京现代综合交通实验室),中华人民共和国交通运输部,江苏南京211100 [3]江苏省低碳与绿色岩土工程重点实验室,江苏南京211189 [4]安徽省水利水电勘测设计研究总院有限公司,安徽合肥230088

出　　处：《岩土工程学报》2024年第S02期210-215,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金面上项目(52078129);综合交通运输理论交通运输行业重点实验室(南京现代综合交通实验室)开放课题(MTF2023009);江苏省研究生科研与实践创新计划项目(SJCX21_0031)。

摘　　要：采用离心模型试验研究了柱状和格栅状搅拌桩联合加固河堤的变形特征。结果表明,采用柱状和格栅状搅拌桩加固软土地基上河堤,可有效控制地基的沉降和减小了软土地基的水平位移,河堤边坡稳定性高。堤顶处沉降最大,尽管施工完成一年后沉降尚未完全稳定,但沉降速率放缓;由于搅拌桩的应力集中效应显著加速了地基的固结速率,根据实测沉降和超静孔隙水压力计算得到施工完成一年时搅拌桩加固地基的固结度分别达到了80%,75%以上。因桩土刚度差异,桩土应力分配呈现模型的应力集中效应,实测的水泥土搅拌桩桩土应力比介于2~3。The centrifugal model tests are conducted to investigate the deformation characteristics of the river embankment on soft ground improved by the combined columnar and grid-form columns.The results indicate that reinforcing a river embankment on soft soil foundations with columnar and grid-form deep mixing columns can effectively control foundation settlement and reduce horizontal displacement,resulting in stability of high slopes.The maximum settlement occurs at the top of the river embankment,and although the settlement is not fully stabilized one year after construction,the settlement rate slows down.The significant stress concentration effects of the mixing columns accelerate the consolidation rate of the foundation.Based on measured settlement and excess pore water pressure,the degree of consolidation of the column-reinforced foundation one year after construction reaches over 80%and 75%,respectively.Due to the stiffness difference between the columns and the surrounding soil,the stress distribution exhibits stress concentration effects in the model.The measured column-soil stress ratio ranges between 2~3.

关 键 词：软土地基 柱状搅拌桩 格栅搅拌桩 河堤 离心模型试验 

分 类 号：TU411[建筑科学—岩土工程]