基坑土钉支护开挖降水对周边建筑物的影响  

Influence of Excavation and Dewatering of Soil Nail Support in Foundation Pit on Surrounding Buildings

作　　者：段佳蕊 杜珊 王安明[1] DUAN Jiarui;DU Shan;WANG Anming(North China University of Water Resources and Electric Power,Zhengzhou,Henan 450046,China)

机构地区：[1]华北水利水电大学,河南郑州450046

出　　处：《水利与建筑工程学报》2023年第5期21-26,84,共7页Journal of Water Resources and Architectural Engineering

基　　金：河南省科技攻关计划项目(182102310745)。

摘　　要：为了探讨基坑土钉支护开挖降水对周边建筑物的影响,以郑州市某基坑土钉支护开挖降水工程为例,使用有限元软件midas GTS NX对基坑施工过程及周边建筑物的存在进行数值模拟,分析基坑开挖降水等工况下土体的水平位移、竖向位移、孔隙水压力、及周边建筑物沉降的变化规律,研究基坑开挖降水对周边建筑物影响,结果表明:随着基坑开挖深度的增加,坑外地表沉降大小和范围慢慢增大,总体呈现先增大后减小最后趋于稳定的变化趋势;随着基坑降水深度的增加,孔隙水压力增大,表层土体中孔隙水压力的变化速率小于深层土体中孔隙水压力的变化速率;建筑物沉降随基坑施工工况的增加逐渐增大,基坑开挖到底时建筑物沉降变化趋势变缓趋于稳定,其数值在规范允许的范围内,表明基坑周边的建筑物处于安全状态。In order to discuss the influence of soil nailing excavation and dewatering on surrounding buildings,taking the soil nail support excavation and dewatering project of a foundation pit in Zhengzhou as an example,the finite element software midas GTS NX was used to numerically simulate the construction process of the foundation pit.The surrounding buildings of the foundation pit were built into a solid model,the changes in horizontal displacement,vertical displacement,pore water pressure,and settlement of the surrounding buildings were analyzed under conditions such as excavation and dewatering.The impacts of excavation and dewatering on the surrounding buildings was further analyzed.The results show that as the excavation depth of the foundation pit increases,the size and range of surface settlement outside the pit gradually increase,showing a trend of first increasing,then decreasing,and finally stabilizing.As the depth of foundation pit dewatering increases,the pore water pressure increases,and the rate of change of pore water pressure in the surface soil is smaller than that in the deep soil.The settlement of buildings gradually increases with the increase of construction conditions of the foundation pit.When the foundation pit is excavated to the bottom,the trend of building settlement changes slows down and tends to stabilize.Its value is within the allowable range of specifications,indicating that the foundation pit is in a safe state.

关 键 词：基坑开挖 土钉支护 数值模拟 降水 周边建筑物 沉降 

分 类 号：TU942[建筑科学—建筑技术科学]