The Reconsolidation Of Disturbed Soft Soil And Its Influence On Metro Tunnel

As more and more underground projects are constructed, the surrounding soil is unavoidable to be disturbed, then it results in the reconsolidation settlement of the disturbed soil. For the tunnel built in soft soil, it would deform along with the reconsolidation of disturbed soil, and the structure of tunnel and the operation of metro would be endangered. Therefore, to study the reconsolidation of disturbed soil and its influence on metro tunnel is very useful for controlling the disturbance of construction and the deformation of metro tunnel.Firstly, this paper summarizes the constructing disturbance of the soil around tunnel which caused by shield tunneling, foundation pit excavating and deep well dewatering separately, analyses the mechanism, the influence factors and the displacing modes of the surrounding disturbed soil. Secondly, it takes shied tunneling for instance, by analyzing measured data, the reconsolidation settlement of disturbed soil is studied, then the method to get reconsolidation settlement from measured data is elementarily brought forward, the relation between time and reconsolidation settlement of disturbed soil in shield tunneling is determined, according to that relation, such pertinent problems as the velocity, length of time and amount of reconsolidation settlement are discussed. Finally, based on analyzing the disturbing mode of underlying soil in shield tunneling and the reconsolidation settlement, then by using the bi-parameter elastic foundation infinite beam model to simulate the interaction between soil and tunnel, and comparing the measured settlement of metro tunnel with nearby ground settlement, the influence on metro tunnel made by the reconsolidation settlement of underlying disturbed soil is studied, and some conclusions are summed up.