Construction scheme design of diaphragm wall deep foundation pit constructed by “top-down” method based on 3D FEM is researched; and design method according to deformation control is put forward. The oversized deep foundation pit of Hutchison Whampoa Ltd. project in China’s Tianjin is calculated and designed as an example. Firstly
structure design of the slabs under vertical load is done. Secondly
three design schemes are put forward based on the structure design and 3-D FEM models of which are established; and every state of each scheme is calculated respectively. The stress and deformation of the diaphragm and slab under different states are obtained. The key state of construction and the weak parts of the whole structure are found out. At last
with consideration of the practical situation
advantages and deficiencies of the schemes are analyzed. Optimal scheme is selected by synthetical consideration.