Analysis of the Load‐Bearing Capacity of the Steel‐Shell Concrete Support Structure Formed by the Construction of the Pipe Curtain Freezing Method

The Sanya estuary passage project is the latest and highly technical underground project after the large shield underground construction, which is of great significance to the construction of the Hainan free trade port and underground space construction innovation. In this paper, we use finite element software to analyze the deformation, stress, and surface settlement of the pipe curtain structure during construction under two conditions (original riverbed line and maximum scour riverbed line) in order to provide guidance for the actual project. Numerical simulations show that due to excavation and unloading, the bottom and top of the pipe curtain structure are subject to tensile stress; the bottom rises, the top settles, and converges in the horizontal direction; under the original riverbed line condition, the displacement values of each index are larger; changing the riverbed line does not change the maximum and minimum main stress of the pipe curtain structure significantly, and the stiffness of the pipe curtain structure can meet the maximum water level and the maximum scour in two unfavorable conditions; the pipe curtain structure can meet the structural. The pipe screen structure can meet the structural load‐bearing requirements. Suggestions for the design and construction of the project: strengthen the thickness of the pipe curtain at the side wall position, that is, use larger diameter steel pipes; do a good job of antiseepage and anticracking of the concrete at the corner of the pipe curtain structure and the side wall position during the construction process.