Influences of riverbed erosion on deformation of large cross-section underwater tunnels

The riverbed erosion caused by runoff changes and sediment conditions has become a new problem for underwater tunnels during its long-term operation. The riverbed erosion overlying the tunnel can lead to changes in burial depth and load, which can cause significant uneven deformation and affect tunnel safety. This study focuses on the deformation response of large cross-section underwater tunnels caused by erosion. The centrifugal test method is used to study the deformation of tunnels caused by multiple erosions. According to the model tests, the internal lining increases the structural stiffness and resists deformation of tunnels caused by erosion unloading. The nonlinear growth of deformation with different erosion depths is analyzed. The muddy clay layer is unfavorable for deformation of tunnels during erosion development. The gap opening of shield segments caused by erosion is analyzed. The internal lining is beneficial for avoiding the disadvantage of segment opening.