Analysis of deformation behavior of deep excavations supported by permanent structure

A database of 31 case histories of wall deformation due to deep excavations supported by permanent structure in Shanghai soft deposit was presented.Deformation behavior of the retaining structure was analyzed.It was shown that the maximum lateral displacement of the retaining wall ranged from 0.1%H to 0.6%H,and the mean value was only about 0.25%H,where H was the excavation depth.Generally speaking,the location of the maximum lateral displacement of the retaining wall occurred near the excavation surface.Furthermore,some factors affecting the deformation of the retaining structure were analyzed,including thickness of soft soil above the wall toe,embedded depth ratio of the retaining structure,system stiffness,factor of stability against basal heave and the location of the first level strut.