近距离浅埋双线隧道的暗挖施工技术

Mining Construction Technology of Double Shallow Tunnels in Close Proximity

受复杂地质、水文及地面荷载的影响,隧道周边围岩应力状态复杂多变,相邻隧道在开挖时相互受到影响。结合深圳轨道交通2号线湾厦站—东角头站区间段左、右线隧道暗挖工程,在施工中采用左右线隧道同方向工作面错开施工、单个隧道工作面采用"双层小导管管棚+小导管超前预注浆加固"的上下台阶法施工技术,降低了近距离双线隧道施工的相互影响,确保了隧道的施工安全稳定。这为类似工程的施工提供了借鉴。

Due to the complicated geology, hydrology and ground loading, the stress of rock around tunnel is complex and changeable. The adjacent tunnels are interacted during excavation. The double line of interval tunnel from Wanxia Station to Dongjiaotou Station of Shenzhen Rail Transit Line 2 is introduced. The double line was mined in the same direction while with different construction sequence. The bench method which uses 'double small duct shed + pilot pre-grouting with small duct' was adopted to mine each line in upper and down sections and reduced the mutual influence of double line with close proximity to ensure the construction safety and stability.