地铁矿山法隧道过砂层的设计与施工

Design and Construction of Bored Metro Tunnels Passing Through Sand Layer

矿山法隧道成功穿越砂层的工程实践越来越多,文章结合广州地铁三号线岗顶站-石牌桥站区间隧道施工,介绍了矿山法隧道过砂层的设计和施工要点。针对区间砂层的分布特点,对砂层影响地段隧道支护参数进行了设计,施工过程中采取了止水和防塌措施,以保证洞内施工和地面建筑物的安全。砂层地段的施工,关键是砂层注浆固结效果,而注浆量和注浆压力是两个关键参数。此外,应在洞内选定合适的出水点进行注浆止水试验以求取合理的注浆参数和注浆设备的配套。严格做好隧道的初期支护和监测工作也是至关重要的环节。

Successful practices of bored tunnels passing through sand layer have been recorded more and more during these years. This paper introduces the construction and design of the running tunnel between Gangding station and Shipai station on Guangzhou metro Line 3 passing through sand layer and built by mining method. And tunnel support parameters were designed according to the distribution characteristics of sand layers on the transit tunnel section. Water-stopping and anti-collapse measures were adopted in the building process to ensure the safety of surface buildings and the safe construction. Grouting consolidation of sand layer was the key to the boring through sand layer section. Grouting amount and pressure were the two key parameters which were acquired through water-stopping tests by grouting on the leaking spots in the tunnel. Rigorous primary support and monitoring were also crucial.