Wind Tunnel Study of a Sudden Change of Train Wind Loads due to the Wind Shielding Effects of Bridge Towers and Passing Trains

Abstract

With crosswind actions, the wind loads on trains can change dramatically as the trains pass through the wake of bridge towers or when two trains pass each other, which will influence the stability of trains and the comfort of passengers. Taking advantage of the developed testing system of a wind tunnel test rig with moving train models, a three-car train model and a single-car train model were used to simulate rail vehicles and road vehicles, respectively. Sudden changes in the aerodynamic forces were measured when the train was passing through the bridge tower or when two trains were passing each other, and the effects of wind speed, train speed, rail positions of trains, and train types on the train’s aerodynamic coefficients were investigated. The analysis showed that for these studied cases, the aerodynamic coefficients of trains all have sudden changes. However, train-induced wind can weaken the sudden change of a train’s aerodynamic coefficients and lengthen the sudden-change region of wind shielding. The effect of sudden changes of wind loads acting on the road vehicle is more obvious than that on the rail vehicle.