三角形钢管塔架风载扭振分析

The analysis on torsional vibration by wind in triangular steel pipe tower

三角形钢管塔架是小型塔架的优选结构型式 ,但存在易产生风载扭振的缺点。通过建立与风向同相位活动坐标系的方法 ,实现了对任意风向下结构风载的分析与计算 ,给出了该塔架风载扭矩的表达式。计算表明 ,以风向变化 6 0°为周期 ,该扭矩在正、负最大值间波动。扭矩的这种变化即是塔架产生扭转振动的原因。阵风风向的急剧变化可能导致塔架发生扭转共振。作为防范结构损坏的基本措施 。

Triangular steel pipe tower is fine type of small scale tower structure. Yet it tends to cause a torsional vibration by wind. By way of setting up movable coordinate system which keeps same phase with wind direction. The analysis and calculation of wind load on the structure at random wind direction are achieved, and also the expression of torque under wind load is given. Results show that the torque by wind waves between maximum and minimum value at the wind changing cycle of 60°. The variation on torque is the very cause of torsional vibration. The gust direction changing abruptly may cause torsional resonance in the tower.So the reliable joints connecting as a guarding measure should be made to prevent structure damages of the tower.