随着黄土地区城市地铁建设规模的不断扩大，新建地铁车站的修建方法也在不断创新，尤其针对城市建筑和地下管线密集区，明挖法施工难以实施的情况下，洞桩法（PBA工法）成了最优选择。然而近年来洞桩法施工过程中造成地面塌陷和管线大变形、开裂等不良影响时有发生，直接威胁城市居民的生命财产安全。因此，研究洞桩法施工地铁车站对周围管线的变形影响具有重要意义。本文以黄土地区西安地铁何家营站为背景，通过现场监测、数值模拟和工程实践相结合的方法，研究车站洞桩法施工各阶段对既有管线和地表变形的影响，主要工作内容及结论如下：

（1）根据工程特点以及周边环境情况，确定监测断面，制定监测方案。通过对现场监测数据的分析，得到雨污水管线和地表在不同施工阶段的变形趋势，提出施工叠加效应是引起管线漏水的关键因素，并确定了本工程雨污水管线的最大沉降控制值。

（2）建立三维有限元数值模型，重点分析了五个关键施工阶段即上导洞施工、下导洞施工、桩梁柱施工、扣拱施工和站厅站台层施工对管线和地表变形的动态变化，结果表明上下导洞施工阶段对管线变形和地表沉降影响最大，其次为扣拱施工阶段。然后，对“上四下二”6个导洞施工顺序进行优化分析，确定出导洞最优施工顺序，即“先上导洞后下导洞，先中导洞后边导洞”。

（3）应用Midas软件模拟管线与车站水平距离和不同夹角工况下，对管线变形的影响，得到管线与车站轴线呈30°时，管线的竖向沉降变形值最小；当管线与车站导洞开挖方向平行时，管线距车站中线越近，管线变形最大。同时分析了不同管道埋深和管径对管线变形的影响，埋深为4~10m内，随着管线埋深的增大管线竖向变形越大，而水平变形越小；管径为400~1600mm内，管径越大管线竖向最大变形越小，而水平变形差别不大。

（4）通过现场监测和数值模拟分析，提出黄土地区洞桩法施工地铁车站时对管线影响范围为2.5L（L为车站主体结构宽度），敏感区域为0~1.5L范围内。建议对处于敏感区域的管线在导洞和扣拱施工阶段加强监测频率。

With the continuous expansion of urban subway construction scale in the Loess Plateau region, the construction methods for new subway stations are also constantly innovating, especially for urban buildings and densely populated areas with underground pipelines. When the open excavation method is difficult to implement, the hole pile method (PBA method) has become the optimal choice. However, in recent years, adverse effects such as ground collapse, large deformation, and cracking of pipelines have occurred during the construction process of the hole pile method, directly threatening the safety of urban residents' lives and property. Therefore, it is of great significance to study the deformation impact of tunnel pile method construction on surrounding pipelines in subway stations. This article takes the Hejiaying Station of the Xi'an Metro in the Loess Plateau region as the background, and combines on-site monitoring, numerical simulation, and engineering practice to study the impact of each stage of station pile method construction on existing pipelines and surface deformation. The main work content and conclusions are as follows:

(1) Based on the characteristics of the project and the surrounding environment, determine the monitoring section and develop a monitoring plan. Through the analysis of on-site monitoring data, the deformation trends of rainwater and sewage pipelines and the surface at different construction stages were obtained. It was proposed that the construction superposition effect is the key factor causing pipeline leakage, and the maximum settlement control value of the rainwater and sewage pipelines in this project was determined.

(2) Establish a three-dimensional finite element analysis model, focusing on analyzing the dynamic changes of pipeline and surface deformation during five key construction stages, namely upper guide tunnel construction, lower guide tunnel construction, pile beam column construction, buckle arch construction, and station hall platform layer construction. The results show that the upper and lower guide tunnel construction stages have the greatest impact on pipeline deformation and surface settlement, followed by buckle arch construction stage. Then, optimization analysis was conducted on the construction sequence of the six pilot tunnels of "upper four lower two" to determine the optimal construction sequence of the pilot tunnel, which is "first the upper pilot tunnel, then the lower pilot tunnel, first the middle pilot tunnel, and then the side pilot tunnel".

(3) Using Midas software to simulate the impact of horizontal distance and different angles between pipelines and stations on pipeline deformation, it was found that when the pipeline is at a 30 ° angle to the station axis, the vertical settlement deformation value of the pipeline is the smallest; When the pipeline is parallel to the excavation direction of the station guide tunnel, the closer the pipeline is to the center line of the station, the maximum deformation of the pipeline occurs. At the same time, the influence of different pipeline burial depths and diameters on pipeline deformation was analyzed. Within a burial depth of 4-10m, as the burial depth of the pipeline increases, the vertical deformation of the pipeline increases, while the horizontal deformation decreases; Within a pipe diameter of 400-1600mm, the larger the pipe diameter, the smaller the maximum vertical deformation of the pipeline, while the difference in horizontal deformation is not significant.

(4) Through on-site monitoring and numerical simulation analysis, it is proposed that the impact range of the tunnel pile method on the pipeline during the construction of subway stations in loess areas is 2.5L (L is the width of the main structure of the station), and the sensitive area is within the range of 0-1.5L. It is recommended to strengthen the monitoring frequency of pipelines in sensitive areas during the construction phase of pilot tunnels and arch buckles.

[1]徐鸣阳. 地铁车站洞桩法对既有管线的影响研究[D].沈阳建筑大学,2018.

[2]刘祖典, 李靖. 黄土的物理力学性质和变形特性[J]. 第四纪研究, 1986 (01) :1-9.

[3]邵生俊, 杨春鸣, 焦阳阳,等. 湿陷性黄土隧道的工程性质分析[J]. 岩土工程学报, 2013, 35 (09) :1580-1590.

[4]邵生俊, 陶虎, 许萍. 黄土结构性力学特性研究与应用的探讨[J]. 岩土力学, 2011,3

(S2) :42-50.

[5]刘均红,陈弦.黄土地区地铁车站深基坑变形监测与分析[J].中国铁路,2009,No. (08) :68-71.

[6]樊胜军,胡长明,刘振江.某深基坑施工期围护结构变形监测与数值模拟分析[J].施工技术,2010,v.39;No.328 (09) :82-84.

[7]Wang X, Song Q, Gong H. Research on deformation law of deep foundation pit of station in core region of saturated soft loess based on monitoring[J]. Advances in Civil Engineering, 2022, 2022: 1-16.

[8]任建喜,谭牧凡.黄土地区地铁车站深基坑变形规律[J].城市轨道交通研究,2021,24（08）:55-58.

[9]刘新, 林源, 张军等.某地铁车站深基坑施工期围护结构及邻近建筑变形监测与分析[J].施工技术,2014,v.43;No.416 (13) :55-58.

[10]任建喜,朱元伟.黄土地区地铁深基坑围护结构变形特性的FLAC软件模拟分析[J].城市轨道交通研究,2014,v.17;No.144 (09) :96-99+123.

[11]吴意谦，朱彦鹏. 兰州市湿陷性黄土地区地铁车站深基坑变形规律监测与数值模拟研究[J].岩土工程学报,2014,v.36;No.273 (S2) :404-411.

[12]黄胜平,韩明华.地铁换乘车站深基坑支护体系测试研究[J].铁道工程学报,2012,v.29;No.164 (05) :58-62.

[13]段立莉,牟林,孙扬.地铁深基坑变形规律及影响因素数值模拟研究[J].中国安全生产科学技术,2011,7 (12) :38-43.

[14]Wang X, Song Q, Gong H. Research on deformation law of deep foundation pit of station in core region of saturated soft loess based on monitoring[J]. Advances in Civil Engineering, 2022, 2022: 1-16.

[15]Mei Y, Li Y L, Wang X Y, et al. Statistical analysis of deformation laws of deep foundation pits in collapsible loess[J]. Arabian Journal for Science and Engineering, 2019, 44: 8347-8360.

[16]贾蓬,高登,刘冬桥.开挖顺序对PBA地铁车站竖向土压力分布影响[J].东北大学学报（自然科学版）,2021,v.42;No.369 (06) :857-863.

[17]李晓霖. 地铁车站洞桩法的数值模拟研究[J]. 地下空间与工程学报,2007,3 (5) :928-932.

[18]杜昌隆,朱雅倩,马路等.PBA暗挖地铁车站洞内地下连续墙施工力学响应分析[J].岩土工程技术,2023,37 (02) :135-141.

[19]曹力桥,王志斌,周丁恒.PBA车站扣拱施工顺序对上部跨河桥沉降影响分析[J].重庆交通大学学报（自然科学版）,2021,40 (01) :79-86+111.

[20]李储军.适用黄土暗挖车站的改进洞桩法研究[J/OL].铁道标准设计:1-10[2021-12-14].

[21]Yong-ping G, Zhao W, Shen-gang L, et al. Key techniques and risk management for the application of the Pile-Beam-Arch (PBA) excavation method: a case study of the zhongjie subway station[J]. The Scientific World Journal, 2014, 2014.

[22]张明聚,晋刘杰,刘义,王鹏程,张卫业.地铁车站洞桩法施工变形风险管控实例分析[J].武汉大学学报（工学）,2016,v.49;No.243 (06) :893-898+910.

[23]Yan M, Ding D Y, Yang X R, et al. 3D Numerical Analysis of Metro Station by PBA Method to Enlarge Existing Large-Size Shield Tunnel[J]. Applied Mechanics and Materials, 2012, 170: 1673-1678.

[24]刘加柱,孙礼超,张壮,徐红,丁银平.地铁车站PBA洞桩法施工力学效应研究[J].地下空间与工程学报,2018,v.14;No.110 (S1) :240-247+307.

[25]Yu L, Zhang D, Fang Q, et al. Surface settlement of subway station construction using pile-beam-arch approach[J]. Tunnelling and Underground Space Technology, 2019, 90: 340-356.

[26]王绍君,刘宗仁,陶夏新.浅埋暗挖隧道施工性态的数值模拟与分析[J].土木工程学报,2007（06）:75-79.

[27]Li T, Li Y, Yang T, et al. Influence of the Large-Span Pile-Beam-Arch Construction Method on the Surface Deformation of a Metro Station in the Silty Clay–Pebble Composite Stratum[J]. Materials, 2023, 16 (7) : 2934.

[28]Liu N, Tong X, Chang L, et al. The Influence of Pile-Beam-Arch Construction on the Stratum and Station Support Structure[J]. Geofluids, 2023, 2023.

[29]邓皇适,傅鹤林,史越等.盾构隧道曲线段掘进引发邻近地下管线变形分析[J].中南大学学报（自然科学版）,2022,53 (08) :3008-3020.

[30]Zhao S W, Li X L, Li X, et al. Analysis of pipeline deformation caused by shield tunnel excavation that obliquely crosses existing pipelines[J]. Arabian Journal of Geosciences, 2022, 15 (3) : 227.

[31]Vorster H H. The emergence of cardiovascular disease during urbanisation of Africans[J]. Public health nutrition, 2002, 5 (1a) : 239-243.

[32]冯国辉,徐长节,郑茗旺,薛齐,杨开放,管凌霄.侧向土体影响下盾构隧道引起上覆管线变形[J].浙江大学学报（工学版）,2021,v.55;No.376 (08) :1453-1463.

[33]陈志敏,范长海,文勇,黄林祥,任益.超浅埋隧道下穿管线沉降变形及控制基准研究[J].公路,2021,66 (09) :371-378.

[34]孙吉主,邓莉,王勇.柔性地下管线受隧道开挖影响的安全性评价[J].长江科学院院报,2018,v.35;No.231 (01) :73-75.

[35]Zhang H, Zhang Z X. Estimating the effects of shield tunnelling on buried pipelines based on a kerr foundation model[C]//New Frontiers in Engineering Geology and the Environment: Proceedings of the International Symposium on Coastal Engineering Geology, ISCEG-Shanghai 2012. Springer Berlin Heidelberg, 2013: 263-268.

[36]李志南,潘珂,王位赢,唐晓菲,马少坤,段智博.双隧道开挖对地表沉降及地埋管线的影响研究[J].广西大学学报（自然科学版）,2021,v.46;No.181 (03) :588-597.

[37]吴为义,孙宇坤,张土乔.盾构隧道施工对邻近地下管线影响分析[J].中国铁道科学,2008,No.99 (03) :58-62.

[38]曹振,雷斌,张丰功.地铁湿陷性黄土暗挖隧道的施工风险及控制措施[J].城市轨道交通研究,2013,v.16;No.126 (03) :97-99.

[39]李超,张陈蓉,卢恺.隧道开挖条件下地埋管线的有限元分析[J].地下空间与工程学报,2016,v.12;No.94 (S1) :219-224.

[40]Klar Assaf and Shoham Etna. Discussion of “Role of Shear Deformability on the Response of Tunnels and Pipelines to Single and Twin Tunneling” by Andrea Franza and Giulia M. B. Viggiani[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2022, 148 (8)

[41]杨秋鸣.城市隧道开挖对周边复杂管线的影响分析[J].建筑技术,2017,v.48;No.573 (09) :

937-939.

[42]Shi X, Cao Y, Rong C, et al. Influence of pipeline leakage on the ground settlement around the tunnel during shield tunneling[J]. Sustainability, 2022, 14 (24) : 16802.

[43]黄明华,周钲霖.双参数地基中隧道下穿既有管线的显式解析解分析[J/OL].安全与环境学报:1-10[2023-04-12].

[44]Xinrong Liu,Yongquan Liu,Zhongping Yang,Chunmei He. Numerical analysis on the mechanical performance of supporting structures and ground settlement characteristics in construction process of subway station built by Pile-Beam-Arch method[J]. KSCE Journal of Civil Engineering,2017,21 (5) .

[45]Xinrong Liu,Yongquan Liu,Wanbo Qu,Yiliang Tu. Internal force calculation and supporting parameters sensitivity analysis of side piles in the subway station excavated by Pile-Beam-Arch method[J]. Tunnelling and Underground Space Technology incorporating Trenchless Technology Research,2016,56.

[46]高海通. 黄土地区地铁隧道施工对地下管线影响的研究[D].西安科技大学,2017.

[47]Zhang K Y, Chavez Torres J L, Zang Z J. Numerical analysis of pipelines settlement induced by tunneling[J]. Advances in Civil Engineering, 2019, 2019.

[48]王丽. 暗挖隧道施工诱发的邻近管线变形规律与控制技术[D].西安科技大学,2017.

[49]王招冰. 洞桩法地铁车站地表沉降及对临近管线影响研究[D].中国地质大学（北京）,2018.

[50]崔达. 洞桩法施工对周边建筑物沉降影响及方案优化[D].中国地质大学（北京）,2019.

[51]杜荣波. 北京地铁某车站洞桩法施工沉降规律研究[D].中国地质大学（北京）,2019.

[52]史晓光. 北京地铁三号线东坝中街站PBA工法施工地表沉降控制研究[D].中国地质大学(北京),2021.

[53]高小州. 黄土地区地铁车站洞桩法施工沉降特性及稳定性研究[D].西安理工大学,2021.

[54]李明皓. 复杂环境富水砂卵石地层PBA工法地铁车站建造沉降机理及控制方法研究[D].北京交通大学,2020.

[55]鲁鑫松. 浅埋隧道不同开挖方式对地表沉降的影响[D].中国地质大学(北京),2017.

[56]寇邦宁. 城市地铁施工对邻近管线的影响[D].北京交通大学,2015.

[57]肖茜. 北京地铁车站洞桩法施工对地表沉降影响的研究[D].中国地质大学（北京）,2014.

[58]梁斌. 长春地铁二号线南关站暗挖施工技术研究与应用[D].吉林大学,2018.

[59]王天彪. 富水地区PBA法地表沉降规律及关键部位施工顺序研究[D].中国地质大学(北京),2018.

[60]陈武. 黄土地层洞桩法暗挖地铁车站设计施工关键技术研究[D].长安大学,2018.

[61]张建国. 洞桩法车站下穿既有管线的地层及结构变位规律研究[D].北京交通大学,2018.

[62]杨光. 城市隧道施工影响下地下管线变形破坏特点及渗漏水影响机理[D].北京交通大学,2017.

[63]孔杰. 盾构隧道下穿既有管线引起地层沉降及管线受力变形规律研究[D].安徽理工大学,2022.

[64]史超凡. 隧道浅埋暗挖法施工对既有管线影响的三维有限元分析[D].湘潭大学,2015.

[65]徐志杰. 浅埋双隧道施工对邻近管线的影响研究[D].北京交通大学,2018.

[66]魏爽. 黏土地层盾构施工对临近压力管线的影响分析[D].安徽建筑大学,2021.

[67]茹国锋. 城市地铁隧道开挖对既有管线的影响分析[D].西安科技大学,2015.