Analysis on running safety of train on the bridge considering sudden change of wind load caused by wind barriers

摘要

The calculation formulae for change of wind load acting on the car-body are derived when a train moves into or out of the wind barrier structure,the dynamic analysis model of wind-vehicle-bridge system with wind barrier is established,and the influence of sudden change of wind load on the running safety of the train is analyzed.For a l0-span simply-supported U-shaped girder bridge with 100 m long double-side 3.5 m barrier,the response and the running safety indices of the train are calculated.The results are compared with those of the case with wind barrier on the whole bridge.It is shown that the sudden change of wind load caused by wind barrier has significant influence on the lateral acceleration of the car-body,but no distinct on the vertical acceleration.The running safety indices of train vehicle with sectional wind barriers are worse than those with full wind barriers,and the difference increases rapidly with wind velocity.