关键词: 盾构隧道, 堤岸变形, 抗滑桩, 切削桩基

Abstract: This study analyzed the disturbance effect on an embankment of large-diameter shield cutting through an anti-slide pile with the goal of ensuring the safety and stability of a levee during the process of shield tunneling. This paper shows how a three-dimensional tunnel–pile foundation–embankment numerical model was established using finite element analysis software. The settlement of a levee and deformation of piles during shield tunneling were analyzed, and the deformations of the piles under different shield thrust values were compared. The results showed that the cutting of anti-slide piles by a shield machine will significantly disturb the upstream slope of a levee. The largest longitudinal displacement occurred at the top of the slope, and the soil around the pile showed obvious settlement. Under the influence of the shield thrust and landslide thrust, the anti-slide pile was characterized by flexure deformation, which formed a slanting “S” curve. The deflection of the anti-slide pile was the most obvious when the cutter head of the shield machine was close to it. The thrust of the shield increased from 0.7 to 0.9 times the static earth pressure, the horizontal displacement of the pile significantly increased, and the displacement of the pile bottom increased by 162% when the cutter head approached the pile foundation. Therefore, when a shield machine cuts through an anti-slide pile, construction parameters such as the advancing speed and mud-water pressure should be strictly controlled to reduce the adverse effect of the shield thrust on the pile.

Key words: shield tunnel, embankment deformation, anti-slide pile, pile cutting