摘要
【目的】研究软弱地层浅埋小间距双线隧道开挖引起的地表沉降及邻近建筑物变形问题,揭示地表沉降的非均匀演化规律,探索混凝土隔离桩对地表沉降的调控作用,进而保障工程安全。【方法】以深圳至大亚湾城际铁路某区间隧道工程为背景,开展数值模拟研究。采用FLAC 3D三维数值模拟软件,建立包含软弱地层、双线隧道、邻近建筑物和混凝土隔离桩的三维有限元模型,模拟分析不同的建筑物类型、基础形式、隔离桩布置方式对小间距双线隧道开挖引起的地表沉降变化规律的影响。【结果】浅埋小间距双线隧道开挖引起的地表沉降具有显著的非均匀性和不规则性,最大沉降通常出现在隧道上方或其邻近区域,两侧沉降较小;不同类型建筑物的变形差异显著,临近隧道上方的建筑物沉降较大;混凝土隔离桩能有效降低土体的主动土压力,进而减小地表沉降和建筑物变形。数值模拟还揭示了隧道掘进参数对沉降变形时空演化的影响,表明合理设计隔离桩可有效控制地表沉降。【结论】在软弱地层浅埋隧道施工中,应充分考虑地表沉降的非均匀性,合理设置隔离桩以有效控制地表沉降。
[Purposes]This study investigates the surface settlement and adjacent building deformation resulting from the excavation of shallow-buried,closely-spaced double-line tunnels in a weak strata.The primary objectives are to elucidate the non-uniform evolution patterns of surface settlement and to explore the regulatory effect of concrete isolation piles on surface settlement,thereby enhancing construction safety.[Methods]A numerical simulation analysis was performed,with a section of the Shenzhen-Daya Bay Intercity Railway tunnel taken as a case study.A three-dimensional finite element model was developed by use of FLAC 3D software,incorporating weak strata,double-line tunnels,adjacent buildings,and concrete isolation piles.This study mainly investigated the effects of varying building types,foundation configurations,and isolation pile arrangements on the excavation of shallow buried,closely-spaced double-line tunnels.[Findings]The results demonstrate that surface settlement induced by shallow-buried,closely-spaced double-line tunnel excavation exhibits pronounced non uniformity and irregularity.The maximum settlement typically occurs directly above or close to the tunnels,while comparatively smaller settlement is observed on either side.Varying settlement magnitudes are observed among different building types,with buildings located in the upper vicinity of the tunnels exhibiting greater settlement.Concrete isolation piles effectively diminish the active earth pressure of the soil,subsequently reducing surface settlement and building deformations.The numerical simulation analysis also elucidates the influence of tunneling parameters on the spatiotemporal evolution of settlement and deformation,demonstrating that properly designed isolation piles can effectively control surface settlement.[Conclusions]The results indicate that,during the construction of shallow buried tunnels in the weak strata,the non-uniformity of surface settlement should be carefully considered,and properly designed isolation piles can effectively control surface settlement.
作者
槐荣国
周凯
许迪
曾柳祁
江益辉
吴金标
HUAI Rongguo;ZHOU Kai;XU Di;ZENG Liuqi;JIANG Yihui;WU Jinbiao(China Railway No.5 Bureau Group Electric Engineering Co.,Ltd.,Changsha 410205,China;China Railway South Investment Group Co.,Ltd.,Shenzhen 518054,China;School of Resources and Safety Engineering,Central South University,Changsha 410083,China)
出处
《交通科学与工程》
2025年第4期113-124,共12页
Journal of Transport Science and Engineering
基金
国家自然科学基金青年基金项目(52308385)
湖南省自然科学基金项目(2025JJ60341)。
关键词
双线隧道
数值模拟
地表沉降控制
软弱地层
隔离桩
double-line tunnel
numerical simulation
surface settlement control
weak stratum
isolation pile
