Investigation of Three-Dimensional Deformation Behavior due to Long and Large Excavation in Soft Clays

By analyzing the extensive field data from a long and large excavation in soft clay, this study investigates the three-dimensional deformation behavior induced by excavation. Significant inhibition effects of corner on both wall deflections and ground settlements were observed and quantified. Thus, a modified function for estimating the distribution of deformation parallel to the excavation is proposed and evaluated. Further analyzing shows that the pipeline settlement can be well estimated by the modified function combining with settlements profile proposed by Hsieh and Ou, and the reduction coefficient is about 0.8; the calculated maximum distortion of the pipeline can provide reliable reference. In addition, it is found that the cement-soil partition walls can also considerably reduce the wall deflections and ground settlements even after the part that is above the excavation base were removed.