基坑开挖对邻近隧道变形影响的解析方法研究  

Analysis on the Influence of Foundation Pit Excavation on the Deformation of Adjacent Tunnels

作　　者：马伟亮 李顺群 叶茂松[3] 黄雄飞[3] Ma Weiliang;Li Shunqun;Ye Maosong;Huang Xiongfei(School of Civil Engineering Tianjin 300384,P.R.China;Tianjin Key Laboratory of Soft Soil Properties and Engineering Environment,Tianjin Chengjian University,Tianjin 300384,P.R.China;Anhui Shuian Construction Group Co.,Ltd.,Hefei 230601,P.R.China)

机构地区：[1]天津城建大学土木工程学院,天津300384 [2]天津城建大学、天津市软土特性与工程环境重点实验室,天津300384 [3]安徽水安建设集团股份有限公司,合肥230601

出　　处：《地下空间与工程学报》2023年第2期446-455,共10页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金(41877251);天津市科技支撑重点项目(19YFZCSF00820);安徽省住房城乡建设科学技术计划项目(2022-YF021,2022-YF152)。

摘　　要：随着城市地下空间工程建设的不断发展,在毗邻既有隧道处进行基坑工程施工已经成为常见的现象。基坑开挖会破坏原有地应力场,进而对邻近隧道产生影响,因此研究相应的应对措施是必要的。基于此,本文将隧道简化为作用在Pasternak地基上的Timoshenko梁,建立了基坑卸荷引起的隧道变形理论计算模型。以合肥大学城深基坑项目为工程案例,分别通过考虑小变形应变特性的Plaxis三维数值模型和理论模型进行计算,并将两个结果分别与现场实测数据进行对比分析。结果表明:模拟计算结果与实测结果基本吻合,最大位移偏差仅为0.6 mm,说明考虑小变形应变特性的本构模型可以很好反映土体应力和变形情况;本文提出的理论模型计算结果与实测结果十分吻合,且理论模型计算结果相比模拟结果更接近实测值,说明所提出的理论模型可以更准确有效地分析基坑开挖效应对侧卧地铁隧道的变形影响。With the continuous development of urban underground space construction,it is a common phenomenon to carry out foundation pit construction adjacent to existing tunnels.Excavation of foundation pit will destroy the original in-situ stress field,and then affect the adjacent tunnel,so it is necessary to study the corresponding measures.Based on this,this paper simplified the tunnel as Timoshenko beam acting on the Pasternak foundation,and established the calculation model of tunnel deformation caused by excavation unloading.Taking the deep foundation pit project of Hefei University City as an engineering case,the Plaxis 3D numerical simulation and theoretical model considering the characteristics of small deformation and strain were used for calculation respectively,and the two results were compared with the field measured data.The results show that the simulation results of Plaxis are basically consistent with the measured results,and the maximum deviation is only 0.5 mm,indicating that the constitutive model considering the characteristics of small deformation and strain can well reflect the stress and deformation of soil;In this paper,the calculated results considering the shear action of the tunnel are in good agreement with the measured results,and the calculated results of the analytical method are closer to the measured results than the simulation results,indicating that the proposed theoretical model can more accurately and effectively analyze the influence of the excavation effect on the deformation of the side-lying metro tunnel.

关 键 词：基坑开挖 隧道变形 理论模型 数值模拟 

分 类 号：U456[建筑科学—桥梁与隧道工程]