Research on adjacent relation and interaction of pits and their construction influence

The purpose of this paper is to research the different influence on the subway station pit in construction, caused by the adjacent pit excavated before and after the station pit. The construction environment is divided into three types: a) no pits around the station; b) the pit around the station is constructed before it; c) the pit around the station will be constructed after it. By 3-D finite element numerical simulation, the displacement of the soil between station and adjacent pit is researched, as well as the internal force of the support of station pit. They are the maximal for case a, the minimal for case c. The influence coverage of the adjacent pit construction is less than the excavation depth. The results can be served as a guide for the design and construction of adjacent pits.