重庆轨道交通四号线头塘地铁站围岩压力分析

Pressure Analysis of Surrounding Rock in Toutang Station of Chongqing Rail Transit Line 4

以重庆轨道交通四号线头塘车站为工程背景,地铁车站属于特大断面浅埋隧道,首创采用预留T字岩梁岩柱隧道施工方法,应用全土柱理论、普氏理论、泰沙基理论、比尔鲍曼理论计算了隧道施工全断面开挖完成后不同埋深工况下围岩的垂直压力、水平压力,分析得出泰沙基理论的计算结果适合于该工程,应用小净距隧道围岩压力理论,计算了T字型断面形成后不同埋深工况下围岩的垂直压力、水平压力。理论分析了隧道施工过程中形成T字型断面以及全断面时顶板的最大拉应力、最大挠度,并计算了隧道顶板不垮落离层时需要的最小支护反力,研究结果为车站施工、支护结构安全提供理论支撑。

This paper uses Toutang station of Chongqing rail transit line 4 as engineering background. Subway station belongs to super big section shallow buried tunnel,and a new construction method of reservation rock beam and rock pillars in model T are adopted in the design of the subway station. The vertical pressure and the horizontal pressure of surrounding rock after the completion of the whole section excavation under different working condition of buried depth are calculated with the theories of soil column,compressive arch,K. Terzaghi and Bill baumann. With analysis,this paper works out that K. Terzaghi theory is suitable for the project,The vertical pressure and the horizontal pressure of surrounding rock after T type section excavation under different working condition of buried depth are calculated with small distance tunnel surrounding rock stress theory. The maximum tensile stress and maximum deflection of roof in the process of tunnel construction formation of T type section and the whole section and the need minimum support reaction force when the tunnel is not caving roof abscission layer are calculated with theoretical analysis in this paper,and the results provide theoretical support for station construction and the supporting structure safety.