含软弱夹层地铁车站拱盖-锚索-注浆组合支护体系研究

Study on Arch Cover-Anchor Cable-Grouting Combined Support System of Subway Station with Weak Intercalation

青岛地铁2号线枣山路车站采用大拱脚拱盖法施工揭示的地质情况与原地质勘探结果不符,原支护体系无法满足地表沉降、拱顶沉降及主体结构受力的要求,因此提出含软弱夹层地铁车站拱盖-锚索-注浆组合支护体系。运用数值分析及稳定性增量的方法研究了注浆加固层厚度、锚索位置及条数、锚索初始预应力对支护效果的影响,确定了该组合支护体系最优的支护参数:注浆加固层厚度为3 m,拱脚及下断面中部各打设1根预应力为200 k N的锚索。

Zaoshan Road station construction of Qingdao Metro Line 2 with large arch foot arch cover method showed that geological conditions is inconsistent with the original geological exploration results,the original support system cannot meet the requirements of ground subsidence,vault subsidence and main structure stress,and the arch cover-anchor cable-grouting combined support system of subway station with weak intercalation was proposed.Numerical analysis and stability increment method was used to study the influence of grouting reinforcement layer thickness,anchor cable location and number, initial prestress of anchor cable on support effect,t he optimum support parameters of this combined support system were determined, in which the thickness of the grouting reinforcement layer is 3 m,and an anchor cable with prestress of 200 kN should be placed in the anchor foot and the middle of the lower section respectively.