地表堆载对既有盾构隧道纵向变形影响  

Effect of ground surface surcharge on longitudinal deformation of existing shield tunnel

作　　者：梁荣柱[1,2,3] 王理想 李忠超 康成 高坤 柯宅邦[4,5] LIANG Rongzhu;WANG Lixiang;LI Zhongchao;KANG Cheng;GAO Kun;KE Zhaibang(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,Hubei,China;Wuhan Municipal Construction Group Co.,Ltd.,Wuhan 430023,Hubei,China;School of Civil Engineering and Architecture,Guangxi University,Nanning 530004,Guangxi,China;Anhui Institute of Building Research&Design,Hefei 230031,Anhui,China;Anhui Province Key Laboratory of Green Building and Assembly Construction,Hefei 230031,Anhui,China)

机构地区：[1]中国地质大学(武汉)工程学院,湖北武汉430074 [2]武汉市市政建设集团有限公司,湖北武汉430023 [3]广西大学土木建筑工程学院,广西南宁530004 [4]安徽省建筑科学研究设计院,安徽合肥230031 [5]绿色建筑与装配式建造安徽省重点实验室,安徽合肥230031

出　　处：《建筑科学与工程学报》2023年第3期130-141,共12页Journal of Architecture and Civil Engineering

基　　金：国家自然科学基金项目(41807262);中国博士后基金面上项目(2019M653308);住房和城乡建设部科学技术计划项目(2021-K-074);安徽省建筑科学研究设计院科研项目(2018JKY-26,2021-52ZC);安徽省住房城乡建设科技计划项目(2020-YF44);绿色建筑与装配式建造安徽省重点实验室开放课题(2021-JKYL-004);武汉市政集团科研项目(wszky202013)。

摘　　要：临时基坑开挖弃土和建筑垃圾引起的地表堆载将对盾构隧道产生不利影响,威胁盾构隧道运营安全,因此有必要评估地表堆载作用下盾构隧道的变形。利用非线性Pasternak地基模型,考虑地基非线性变形特点,通过接头非连续盾构隧道计算模型反映盾构隧道环间接头的影响,利用两阶段法,推导得到地表堆载作用下盾构隧道纵向变形简化计算方法。首先,通过Boussineq解求得地表堆载下盾构隧道所受附加荷载;其次,将附加荷载作用于盾构隧道,结合接头非连续盾构隧道模型推导得到盾构隧道在地表堆载作用下的纵向变形方程,并使用有限差分法对方程进行求解,最后结合2个工程案例验证了所提方法的合理性。结果表明:增加盾构隧道环间接头的转动刚度对减小隧道沉降的作用较小,但可以有效减小接头张开量;增加堆载长度会同时增大盾构隧道沉降量和沉降范围,而增加堆载宽度只会导致隧道沉降量缓慢增加,但不会引起隧道沉降范围增大;增大堆载边界线到隧道轴线的距离会有效减少堆载引起的沉降量。The ground surface surcharge caused by the dumped soil from temporary excavation and construction wastes have adverse impacts on the shield tunnel and can threaten the safe operation of the shield tunnel.Therefore,it is necessary to evaluate shield tunnel deformation subjected to surface surcharge.The nonlinear characteristics of soil deformation were considered by nonlinear Pasternak foundation model.The influence of shield tunnel segmental ring joint was considered by the joint discontinuous shield tunnel calculation model.Using the two-stage method,a simplified calculation method of longitudinal deformation of shield tunnel under surface surcharge was derived.Firstly,the additional pressure imposed on the shield tunnel was estimated by Boussineq s solution.Secondly,based on the joint discontinuous shield tunnel model,the longitudinal deformation equation of the shield tunnel under surface surcharge was derived by imposing the additional pressure,and the equation was solved using the finite difference method.Finally,the rationality of the proposed method was verified by two engineering cases.The results show that the increase of the rotational stiffness of shield tunnel segmental ring joint has little effect on the reduction of the tunnel settlement,but it can effectively reduce the joint opening.Increasing the surcharge length will increase the settlement and settlement range of the shield tunnel at the same time,while increasing the surcharge width will only lead to a slow increase in the tunnel settlement but will not increase the tunnel settlement range.The increase of the distance between the surcharge boundary line and the tunnel axis will effectively decrease the settlement caused by surcharge.

关 键 词：地表堆载 盾构隧道变形 非线性Pasternak地基模型 接头非连续盾构隧道计算模型 

分 类 号：TU344[建筑科学—结构工程]