沪昆高铁北盘江特大桥导风栏杆防风效果风洞试验研究

为满足列车在25 m/s风速下以设计速度350 km/h安全通过桥梁,以沪昆高铁北盘江特大桥为工程背景,研发一种桥梁防风装置—导风栏杆。每根导风栏杆由挡风面、导风角、通风孔、加强肋、安装孔构成,挡风面近似为一个扇形结构,上部有导风角,挡风面上部均布通风孔。每根导风栏杆以一定的间距排列,通过螺栓与下部预埋组件相连。通过风洞试验和风-车-桥耦合分析对导风栏杆进行防风效果验证。结果表明:导风栏杆的应用解决了列车在大风情况下的全速安全运行问题,同时提高了列车的乘坐舒适性。导风栏杆兼具挡风、导风、栏杆功能于一体,同时发挥了桥梁防风、行人安全防护的功能。大部分风通过带折角的倾斜导风叶片进行转向,减小了风荷载对导风栏杆的受力,同时减小主梁的受力。

Wind Tunnel Test of Wind Guide Railing Effect of Beipanjiang Major Bridge on Shanghai-Kunming High Speed Railway

To allow the train to pass the bridge safely at a design speed of 350 km/h against 25 m/s wind speed, a kind of bridge wind protection device of wind guide railing is developed with reference to Beipanjiang major bridge on Shanghai-Kunming high speed railway. Each guide rail consists of windscreen, guide angle, ventilation hole, reinforcing rib and installation hole. The windscreen is approximately a fan-shaped structure with a guide angle and ventilation holes on the upper part. Guide rails are arranged with a certain interval and connected to the pre-buried lower assembly by bolts. The wind protection effect of the device is verified by means of wind tunnel test and wind-vehicle-bridge coupling analysis. The results show that the application of the wind guide railing can ensure the safe train running at a full speed in the case of strong wind and improve the ride comfort. The wind guide railing integrates the functions of windscreen, wind guide and railing. Meanwhile, it protects both the bridge and pedestrians. Most of the wind is sheered off by the inclined wind guide blades with folded angles to reduce the wind load on the wind guide railing and the stress on the main beam.