管幕作用下大断面箱涵开挖面稳定性影响因素研究  

Study on the Influence Factors of Excavation Face Stability of Large Section Box Culvert Under the Action of Pipe Curtain

作　　者：刘宇 袁齐虎 杨新安[1] 李路恒 张兴其 LIU Yu;YUAN Qihu;YANG Xinan;LI Luheng;ZHANG Xingqi(The Key Laboratory of Road and Traffic Engineering of Ministry of Education,Tongji University,Shanghai 201804,China;The Fourth Engineering Co.,Ltd.of CTCE Group,Hefei Anhui 230012,China;Hefei Planning Design Institute Co.Ltd.,Hefei Anhui 230031,China)

机构地区：[1]同济大学道路与交通工程教育部重点实验室,上海201804 [2]中铁四局集团第四工程有限公司,安徽合肥230012 [3]合肥市市政设计研究总院有限公司,安徽合肥230031

出　　处：《铁道建筑技术》2024年第8期40-44,共5页Railway Construction Technology

基　　金：安徽省住房城乡建设科学技术计划项目(2021-YF45)。

摘　　要：管幕作用下大断面箱涵开挖面稳定性受多种施工工况影响,需对其影响因素开展系统研究。依托合肥市滨湖科学城庐州大道浅埋隧道段实例工程,构建大型三维精细化数值模型,分析钢管幕群、支护压力以及顶推距离、开挖方式和管幕滞空距离等因素影响下开挖面稳定规律。结果表明:(1)钢管幕群对于维持开挖面稳定性起重要作用,并且管幕结构未连接更有利于维持开挖面的稳定性。(2)当支护压力小于80 kPa时,开挖面纵轴线方向位移量随支护压力的增大而逐渐减小,并逐渐趋于稳定状态;当支护压力大于90 kPa时,开挖面状态易呈倒“S”形。(3)先从两侧开挖,再进行中间开挖的施工方法利于维持开挖面稳定。(4)随着管幕滞空距离增加,开挖面纵轴线方向外移量逐渐增大,不利于开挖面稳定。The stability of excavation face of large-section box culvert under the action of pipe curtain is affected by various construction conditions,which is necessary to carry out systematic research on its influencing factors.Based on the shallow buried tunnel section of Luzhou Avenue in Hefei Binhu Science City,this paper constructs a large-scale three-dimensional refined numerical model to analyze the stability law of excavation face under the influence of factors such as steel pipe curtain group,support pressure,jacking distance,excavation method and pipe curtain stagnation distance.The results show that:(1)the steel pipe curtain group plays an important role in maintaining the stability of the excavation face,and the unconnected pipe curtain structure is more conducive to maintaining the stability of the excavation face.(2)When the support pressure is less than 80 kPa,the displacement of the longitudinal axis of the excavation face gradually decreases with the increase of the support pressure,and gradually tends to be stable.When the support pressure is greater than 90 kPa,the excavation face state is easy to be inverted′S′shape.(3)The construction method of excavating from both sides first and then excavating in the middle is conducive to maintaining the stability of the excavation face.(4)With the increase of the stagnation distance of the pipe curtain,the outward displacement of the longitudinal axis of the excavation face gradually increases,which is not conducive to stability.

关 键 词：管幕箱涵工法 开挖面稳定 影响因素 数值模拟 

分 类 号：U455.47[建筑科学—桥梁与隧道工程]