软土地区大断面矩形顶管浅覆土下穿高速变形控制分析研究

Settlement Control Investigation on Large Quasi-Rectangular Pipe Jacking Tunnelling under Expressway with Shallow Overburden in Soft Soil Areas

以上海市陆翔路—祁连山路贯通工程大断面矩形顶管下穿S20外环高速为背景,探讨了控制顶管浅覆土下穿高速变形的加固措施。介绍了钢管幕加固在本工程中的设计与工程实施情况,并采用三维数值仿真分析了下穿S20外环高速施工引起的变形情况,预测变形规律及结果与监测断面数据吻合性较好。工程的实施论证了采用钢管幕加固控制大断面顶管浅覆土下穿高速的可行性,可为今后软土地区类似顶管下穿高速工程提供借鉴。

Based on the connecting project of Luxiang Road-Qilianshan Road in Shanghai,settlement control measures of large quasi-rectangular pipe jacking tunnelling under S20 expressway with shallow overburden is discussed.Design and engineering application of steel pipe roof is introduced.The deformation caused by high-speed construction under the outer ring of S20 is analyzed by using three-dimensional numerical simulation.The numerical prediction of S20 expressway settlement coincides with the in-situ measured data.Successful application of this project confirms the feasibility of steel pipe roof to attenuate the unfavorable effect caused by large Quasi-Rectangular Pipe Jacking.Thus high referential value will be offered for future engineering projects undercrossing expressway in soft soil areas.