基于风-车-桥(线)耦合振动的风屏障防风效果研究

Study on wind shielding effect of wind screens based on coupling vibration theory of wind-vehicle-bridge(lines) systems

为考察风屏障的防风效果,通过风洞试验测试平地路基、高路堤、桥梁三种典型线路上设置不同风屏障情况下车辆的气动力系数,采用风-车-桥(线)耦合振动的分析方法研究车辆的动态响应,讨论风屏障高度、车辆线路位置及线路构造形式等因素的影响。结果表明,风屏障可有效地降低强风作用下车辆的响应,平地路基上设置2.05m风屏障时,车辆运行的瞬时临界风速可达50m/s;车辆的轮重减载率、倾覆系数及竖向加速度对车辆线路位置较为敏感;线路构造形式对背风侧车辆响应影响较大,风屏障高度相同时,高路堤上的防风效果较好。

In order to investigate the wind shielding effect of wind screens for wind-vehicle-bridge （lines） systems, the aerodynamic coefficients of vehicle were measured by wind tunnel tests, in which different wind screens were respectively installed on three typical railway forms including flat lands, high embankments and bridges, The dynamic responses of vehicles were investigated by the coupling vibration analysis of wind-vehicle-bridges （lines） systems, The influence of wind screen height, vehicle rail position and infrastructures type was discussed to indicate the effect of wind screens. The results show that the response of vehicle under the action of strong crosswind can be significantly reduced by wind screens, and the transient critical wind speed for flat ground railway is up to SOm! s when the height of wind screen is 2.0Sm. The wheel unloading rate, overturning coefficient and vertical acceleration of vehicles are more sensitive to the position of vehicle, and the response of vehicle along windward rail is larger than that of leeward rail. The type of infrastructure has a greater effect on the leeward vehicle response. The wind shielding effect of wind screen installed on high embankment railway is better when the height of wind screen is similar.