地铁隧道内独立泵房冷冻法施工技术

FREEZING CONSTRUCTION TECHNOLOGY FOR INDEPENDENT PUMP HOUSE IN SUBWAY TUNNEL

对于单独设置在主隧道中的废水泵房,当采用冷冻法进行加固开挖时,在狭小空间内采用常规倒挂井壁法进行开挖和支护较难实施。同时,泵房位于隧道正下方,土体冻融对已成型的隧道有较大的影响。结合冷冻法施工技术及现场条件,提出了一种采用钢环护壁+螺栓连接的方法,减小了对空间的占用,省掉了喷射混凝土工序,加快了施工进程。采用对压力、沉降、变形多重监测方式,减小对既有结构的影响。

For freezing reinforcement of the separate wastewater pump house in a main tunnel in excavation,it is difficult to conduct the conventional shaft wall inversion for excavation and support in a narrow space.Meanwhile,the pump house is below the tunnel,so soil freezing and thawing have significant impact on the formed tunnel.In conjunction with the freezing construction technology and site conditions,an approach of wall protection with steel rings+bolting was proposed,to reduce the occupation of space,avoid shotcrete construction and accelerate the construction.The pressure,settlement and deformation were monitored to reduce the impact on existing structures.