内隔墙长度对抽水引发基坑围挡侧移的影响  

Effect of buttress wall length on retaining wall deflection induced by dewatering

作　　者：曾超峰[1,2] 廖欢 李淼坤 薛秀丽 梅国雄[2] ZENG Chao-feng;LIAO Huan;LI Miao-kun;XUE Xiu-li;MEI Guo-xiong(Hunan Provincial Key Laboratory of Geotechnical Engineering for Stability Control and Health Monitoring,Hunan University of Science and Technology,Xiangtan 411201,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Guangxi University,Nanning 530004,China)

机构地区：[1]湖南科技大学岩土工程稳定控制与健康监测湖南省重点实验室,湖南湘潭411201 [2]广西大学工程防灾与结构安全教育部重点实验室,广西南宁530004

出　　处：《浙江大学学报（工学版）》2021年第12期2252-2259,共8页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(51708206,51978261);湖南省自然科学基金资助项目(2020JJ5193,2020JJ4300);湖南省教育厅资助项目(20A190,17B097).

摘　　要：结合实际工程地质条件,开展三维数值分析,研究内隔墙对限制开挖前抽水引发基坑围挡变形的有效性,探究在不同抽水深度与不同围挡嵌固比条件下,内隔墙长度对基坑围挡变形控制效果的影响.结果表明:随内隔墙长度增大,内隔墙对基坑围挡变形的控制效果增强.在不同抽水深度条件下,内隔墙对基坑围挡变形的控制效率不同,当抽水深度大于20 m时,内隔墙长度须大于基坑宽度的0.75倍或者采用全贯通式内隔墙,以取得较好的变形控制效果;当抽水深度小于10 m时,可将内隔墙长度设置为基坑宽度的0.25~0.50倍,预期也可取得较可观的变形控制效果.在不同围挡嵌固深度条件下,内隔墙对变形的控制效率不同,延长基坑围挡嵌固深度能增强内隔墙在抽水深度范围内的变形控制效果.A series of three-dimensional finite element numerical models were developed,on the basis of practical engineering geological conditions,to explore the effectiveness of buttress wall in reducing retaining wall deflection caused by pre-excavation dewatering.The influence of the buttress wall length on its deformation control effect under different dewatering depth and different penetration ratios were revealed.Results show that the deformation control effect of buttress wall on retaining wall is enhanced with the increase of the buttress wall length.The control efficiency of buttress wall on retaining wall deformation is different under different dewatering depth.When the dewatering depth is greater than 20 m,the length of the buttress wall should be over 0.75 B or set cross wall to totally connect two opposite retaining walls to achieve a satisfactory deformation control effect,where B is the foundation pit width.However,when the pumping depth is less than 10 m,the buttress wall length can be set as 0.25-0.5 B,and at this moment,a significant deformation control effect can be also achieved.Besides,control efficiency of buttress wall on deformation is different under different penetration depth of retaining wall.Extending the penetration depth of the retaining wall can enhance the deformation control effect of the buttress wall in the range of dewatering depth.

关 键 词：软土地基 基坑抽水 围护结构侧移 内隔墙 有限元计算 嵌固比 

分 类 号：TU473[建筑科学—结构工程]