Abstract:Cofferdam is widely used as a common temporary enclosure structure in the construction of modern bridge foundation pit. It is necessary to design and study cofferdam to ensure the safety. The PLC pile cofferdam is used as the water retaining structure of the pier foundation, which not only enhances the water sealing effect of the locked steel pipe pile, but also saves the steel and reduces the construction cost. Taking the PLC pile cofferdam used in the construction of the main pier of a landscape bridge in Hainan as an example, the PLC pile cofferdam in the deep foundation pit is analyzed. Combined with the finite element method and theoretical formula, the design scheme is analyzed to ensure the safety and stability of the deep foundation pit structure in the construction.