紧邻铁路偏压基坑长短桩围护结构受力变形分析  

Test Analysis of Stress and Deformation of Long-Short Pile Retaining Structure Adjacent to Railway Asymmetric Load Foundation Pit

作　　者：龚宏华 周旭明 詹刚毅[3] 石钰锋[2,4] 胡俊浩 蒋亚龙 Gong Honghua;Zhou Xuming;Zhan Gangyi;Shi Yufeng;Hu Junhao;Jiang Yalong(Jiangxi Local Railway Development Co.,Ltd.,Nanchang 330001,China;Jiangxi Key Laboratory of Geotechnical Infrastructure Safety and Control,East China Jiaotong University,Nanchang 330013,China;China Railway Shanghai Design Institute Group Co.,Ltd.,Shanghai 200070,China;East China Jiaotong University Architectural Design Institute Co.,Ltd.,Nanchang 330013,China)

机构地区：[1]江西地方铁路开发有限公司,江西南昌330001 [2]华东交通大学江西省岩土工程基础设施安全与控制实验室,江西南昌330013 [3]中铁上海设计院集团有限公司,上海200070 [4]华东交通大学建筑设计院有限公司,江西南昌330013

出　　处：《华东交通大学学报》2023年第2期1-8,共8页Journal of East China Jiaotong University

基　　金：国家自然科学基金面上项目(42177162)。

摘　　要：紧邻铁路偏压基坑施工对铁路运营影响大,需严格控制其变形,以减小对铁路的影响,因此对基坑围护结构的设计通常“偏保守”,存在优化的可能。为探究偏压基坑中围护结构优化的可能,以某工程为依托,分别对铁路两侧的等长桩围护结构与长短桩围护结构的变形与内力进行了测试,比较分析了两侧围护结构的实测结果。结果表明:在本工程中,左右两侧基坑变形较小,均在可控范围内,等长桩围护结构与长短桩围护结构均可保证基坑与铁路安全。与等长桩围护结构相比,长短桩围护结构的桩身最大水平位移与弯矩出现了增长,水平位移最大增长了0.25 mm,桩身弯矩最大增长了10.14 kN·m,两者增长量均较小,长短桩围护结构具有良好的支护效果。长短桩围护结构紧邻偏压侧的桩身水平位移与弯矩大于远离偏压侧,但两者相差较小,偏压荷载对长短桩围护结构的影响较小。Construction of asymmetric load foundation pit adjacent to railway has a great impact on railway operation,and its deformation should be strictly controlled to reduce the impact on railway.Therefore,the design of foundation pit retaining structure is usually"conservative",and there is a possibility of optimization.In order to explore the possibility of retaining structure optimization in asymmetric load foundation pit,based on a project,the deformation and internal force of the equal-length pile retaining structure and the long-length pile retaining structure on both sides of the railway were tested,and the measured results of the two sides of the pile retaining structure were compared and analyzed.The results show that in this project,the deformation of the left and right sides of the foundation pit is small,both within the controllable range,and both the equal-length pile enclosure structure and the long-length pile enclosure structure can ensure the safety of the foundation pit and railway.Compared with the equal-length pile envelope,the maximum horizontal displacement and bending moment of the long and short pile envelope increase with the maximum horizontal displacement increase of 0.25 mm and the maximum bending moment increase of 10.14 kN·m,both of which are small.The long and short pile envelope has a good supporting effect.The horizontal displacement and bending moment of the short and long pile envelope adjacent to the asymmetric load side are larger than those far from the asymmetric load side,but the difference between them is small,and the influence of the asymmetric load on the short and long pile envelope is small.

关 键 词：偏压荷载 围护结构 长短桩 位移 内力 

分 类 号：TU74[建筑科学—建筑技术科学]