English：

Compared with regular foundation excavation, specialshaped deep foundation excavation face greater design and construction risks due to their irregular characteristics, which are prone to causing serious damage to adjacent buildings (structures), especially in deep waterrich sand layers with high groundwater levels and strong erosion. However, there is still a lack of research on the construction safety technology of specialshaped deep foundation excavation adjacent to sensitive buildings in this special stratum. Based on a subway transfer station project adjacent to a highrise building in Nantong, Jiangsu Province, the main construction difficulties faced during the implementation of the specialshaped foundation excavation are analyzed, including ensuring the water tightness of the diaphragm wall and the stability of the foundation excavation, protecting the adjacent buildings, and reducing the adverse effects of pumping. Therefore, the construction technology of specialshaped diaphragm wall, the stability and deformation control technology of deep foundation excavation, the key technology of adjacent sensitive building protection, and the control technology of pumping influence in deep waterrich sand layers are put forward, which effectively ensures the safety of the foundation excavation and building.