轨道交通盾构隧道下穿铁路线施工技术分析

Analysis on Construction Technology of Rail Transit Shield Tunnel underneath Railway Line

西安市轨道交通L3胡家庙站—石家街站盾构区间穿越陇海铁路线总体工程建设风险为Ⅰ级。为了解决黄土地区盾构下穿陇海铁路施工中地面沉降、管片上浮等施工技术难题,通过风险分析和盾构试验段施工,获得如下结论:采取地面沉降和管片上浮控制、监控测量等技术措施,使得Ⅰ级风险点累计最大沉降为-4.39 mm,Ⅱ级风险点累计最大沉降为-15.2 mm,满足产权单位-6 mm和-20 mm沉降控制要求,保证既有线安全,取得良好的经济效益和社会效益。

With background of Xi'an Rail Transit L3 project,the overall construction risk of shield interval of Hujiamiao Station and Shijiajie Station crossing Longhai Railway is evaluated as Grade Ⅰ.In order to solve the problem of construction technology such as land subsidence and pipe floating in the construction of the Longhai Railway under shield machine in loess area,according to the shield across Longhai Railway risk analysis and the shield test section construction,the conclusions are obtained as followed:taking use of some technical measures such as ground subsidence,segments floating control and monitoring measurement,the cumulative maximum settlement of the Grade Ⅰ risk point is-4.39 mm,and the same value of the Grade Ⅱ risk point is-15.2 mm,which can meet the settlement control requirements of the property units-6 mm and-20 mm and can ensure the security of the existing line and moreover achieve good economic & social benefits.