地铁单拱大跨暗挖车站拱墙开洞接口处理技术

摘要

Due to the characteristics of large span single arch of Chongqing metro station where subsidiary portal is made in the arch wall of station main tunnel, a free face is created in the main body and the arch the construction risk of tunnel arch wall opening and prepare steel frame supporting immediate after excavation, this paper proposes the tilted two-dimensional steel arch frame supporting system based on engineering practices and introduces segmental construction process with supporting steel frame put in place with the progress of the opening. In addition, the reliability of the technology is verified by the analysis of field construction monitoring data.%基于重庆地铁暗挖车站单拱大跨的特点，车站主体隧道在其拱墙部位开附属洞门时，势必会在主体与附属接口拱部形成临空面，尤其是大断面附属接口形成的长大临空面存在较大的施工风险；为有效降低隧道拱墙开洞的施工风险，实现“随挖随支、钢架步步封闭”的施工原则，结合工程实际提出倾斜二维钢架接口支撑体系，详细介绍大跨拱墙开洞时支撑钢架步步封闭的分段拼装施工工序，并通过对现场施工监测数据的分析，验证该技术的可靠性。