大直径管线横穿地铁基坑支护措施研究

Study on Supporting Measures for Large Diameter Pipelines Crossing Subway Foundation Pit

地铁车站多在城市闹市区跨路口设置,该区域也是各种地下管线相对最为密集的区域。当管线与明挖法施工的车站结构冲突时,一般采取避让或迁改方式进行处理。本文结合地下深埋电力管线横穿地铁车站基坑的情况,在无法采取避让和迁改措施时,通过设置双排桩和增加钢支撑及换撑的方式有效减小了桩体内力及变形,满足了规范要求。同时通过对桩间土体采取平面型钢钢架、双排钢筋网和土钉等概念设计的加固措施保证其在基坑开挖和主体浇筑过程中的稳定性,有效保障了结构施工期间的基坑安全。本文解决了在大直径管线横贯地铁车站基坑时支护结构如何设计的工程难题,可为今后类似工程的应用提供经验借鉴。同时,针对大直径管线其自身特点探索相应的悬吊措施和悬吊设备也可成为今后的研究重点。

The subway stations are mostly located in the intersections of cities in the downtown area. The area is also the most densely packed area of underground pipelines. When the pipeline is in conflict with the structure of the station constructed by open cut method, it usually takes the form of avoidance or relocation. In this paper, combined with the condition of underground deep buried power pipeline crossing the foundation pit of subway station, the force and deformation problem of large spacing retaining pile was solved by using double row pile and the supporting measures of increasing steel support. At the same time, some measures adopted in conceptual design, such as plane steel frame, ＂double row reinforcement mesh and soil nailing, were taken to reinforce the side wall of foundation pit, and the safety and stability of foundation pit were effectively guaranteed in construction. This paper solved the engineering problem of how to design the support structure for the large diameter pipeline while crossing the subway station foundation pit, which could be used as reference for the application of similar engineering in the future. Meanwhile, aiming at the characteristics of large diameter pipelines, the corresponding suspending measures and suspended equipment could also be the focus of future research.