列车交会条件下高铁隧道衬砌掉块气动力行为OA

Lining spalling in high-speed railway tunnels has become increasingly prominent due to long-term operation,posing a serious threat to train operational safety.Compared to single-train operation,train crossing within tunnels generates more complex aerodynamic effects,making the aerodynamic behavior of spalling blocks under such conditions particularly noteworthy.By utilizing the dynamic overset grid method and IDDES turbulence modeling,a refined 3D gas-solid coupling model was established.This model incorporates the lining spalling block,high-speed train,tunnel,and air under train crossing conditions.It enables accurate simulation of the transient motion process of spalling blocks and systematically investigates the influence of the spalling timing on the block's trajectory,attitude evolution,and force characteristics.The research findings indicate that:1)Spalling blocks exhibit significant displacement in the positive X-direction(exceeding 2.5 m)during tail-head and tail-middle crossing.Conversely,displacement in the negative X-direction is pronounced during middle-head and tail-tail crossings.The maximum Z-direction displacement(0.6 m)occurs during tail-middle crossings.2)The largest rotation angle occurs during head-head crossings,whereas the most stable motion is observed during middle-middle crossings.3)In tail-middle crossing scenarios,the vorticity distribution around the spalling block is complex and changes markedly over time,leading to larger displacements and rotation angles.In contrast,middle-middle crossing scenarios feature smaller and more uniformly distributed vorticity around the block,resulting in more stable motion.This research provides a theoretical foundation for the dynamic monitoring of lining defects and the prevention and control of operational safety risks in high-speed railway tunnels.