Subway station deep foundation pit construction method under water-rich geological condition

The invention relates to the technical field of subway construction, in particular to a subway station deep foundation pit construction method under the water-rich geological condition. The construction method comprises the following steps that S1, a construction site is planned and arranged; S2, pipeline cutting and changing are carried out; S3, underground diaphragm wall construction is carried out; S4, foundation pit excavation numerical simulation is carried out; S5, a foundation pit is excavated, wherein S51, the foundation pit is dewatered; and S52, earth excavation is conducted. According to the construction method, influence analysis and scientific simulation analysis of complex geological conditions on the subway station are carried out, such that risks possibly encountered in the construction process can be avoided, the construction safety is improved, the construction quality and the construction process safety are guaranteed, construction accidents are avoided to the maximum extent, and the constr