以主跨为730m的钢主梁斜拉桥为对象,研究了栏杆、汽车等对汽车一钢主梁桥面系统的气动三分力系数的影响。进行了1:60缩尺模型试验,开展了桥面无车状态、桥面有车状态和施工状态下的75个试验工况节段模型测力试验研究,并利用获得的三分力系数进行了全桥静风响应分析。结果表明:栏杆增加了主梁的阻力系数;桥面车辆的存在使车一桥系统的阻力系数降低,升力系数的绝对值变小,升力矩系数绝对值变小;3种状态中三分力系数越大,相应的侧向、竖向和扭转响应越大;随风攻角变化,栏杆、汽车对车一桥系统阻力、升力和升力矩的影响各不相同。
By focusing on the cable-stayed bridge of main steel girder with a span of 730 m, it was studied how bridge-railings and automobiles influenced three-component of aerodynamic force coefficient of vehicle-main steel girder bridge deck system. The three-component of aerodynamic force of a 1 : 60 scale sectional model was tested for the 75 test cases including bridge deck without vehicles, bridge deck with vehicles and construction stage. The aerostatics response analysis of the full-bridge was done using the three-component force coefficient. The result indicates that bridge-railings raise drag force coefficient of main girder; vehicles lead drag force coefficient to decrease and reduce the absolute values of both lifting-force coefficient and moment coefficient; in all three conditions, the bigger the three component force coefficient is, the bigger the corresponding lateral displacement, vertical displacement and torsional displacement are. With the change of wind attack angle, the influences of bridge railings and automobiles on vehicle-bridge system drag force, lifting-force and its moment are different from each other.