Abstract:

To deal with the complex-stated problem of tunnel construction in the fifth building site of No.7 Metro Line in Shanghai, the sedimentation of large caliber conduit buried in complex soil caused by the surrounding soil gathered in the construction and second concretion is discussed. The current of sedimentation along the change of soil layer, range of disturbed soil layer, depth of conduit and change of the caliber about the large caliber conduit buried in complex soil is analyzed. This is done with the solution to non-completed concretion-girder and Lichi difference method. The juncture between two conduits to provide guidance to similar projects in which sedimentation about conduit bury in the soil is caused by concretion or second concretion of the soil is also analyzed. 

Key words: sedimentation; large caliber; buried conduit; second concretion; Lichi difference method