Abstract:

The construction of metro station has characteristics such as adjacent buildings, dense pipelines and rich groundwater. In order to solve the construction problem PBA metro station without water, the limit ground area and surrounding environment, a comprehensive dewatering method combined with PBA method is used in Shilihe Metro Station on Beijing Metro Line No. 17 in complex environment, and the light well point in tunnel as main mean and vacuum tube on ground as assistant are adopted. The dewatering effects show that: (1) The ground tube well effectively controls the groundwater level of each layer to ensure the normal construction of the vertical shaft. (2) The horizontal radiation wells, as the main precipitation method for construction cross passageway and pilot tunnel excavation, effectively reduces the groundwater level with large water volume such as confined water within the excavation range, which provides a water-free environment for PBA station. (3) The inclined shaft is used as an auxiliary dewatering construction method in tunnel to dewater the inter-layer diving and interfacial residual water.

Key words: metro station, complex environment, PBA station, dewatering, tube well, light well point