台风区桥梁格构式高支架风洞试验研究

Wind Tunnel Test Study on Lattice⁃Type High⁃Bracket of Bridge in Typhoon Area

在研究桥梁格构式高支架抗台风稳定性中,气动力试验和粒子图像测速试验成为关键方法。通过风洞测力试验,得到格构式高支架静力在不同条件下三分系数的数据。采用PIV技术研究格构式高支架受风向影响的规律,并对水平和竖向平面流场下的格构式高支架模型进行可视化分析。研究结果表明:在抗风计算中需要综合考虑静风荷载对阻力、升力和扭力的影响;六腿格构式高支架模型的涡心处涡旋强度和湍动能小于四腿格构式高支架模型;支架构件之间存在相互作用,需要针对风荷载下构件间的影响提出解决方案,进行数值模拟时需考虑格构式高支架的空间三维特性对计算结果的影响。本文研究了格构式高支架抗台风稳定性的特性,为提高桥梁施工安全性提供了重要参考。

Aerodynamic test and particle image velocimetry test become the key methods in studying the stability of bridge lattice⁃type high⁃bracket against typhoon.The wind tunnel force measurement test is used to obtain the data of the three⁃part coefficient of the static force of the lattice⁃type high⁃bracket under different conditions.The PIV technique is used to study the law of lattice⁃type high⁃bracket affected by wind direction,and the lattice⁃type high⁃bracket model under horizontal and vertical plane flow field is visualized and analyzed.The results show that the effects of static wind loads on resistance,lift and torsion need to be considered comprehensively in the wind resistance calculation.The vortex strength and turbulent kinetic energy at the vortex center of the six⁃legged lattice high⁃bracket model are smaller than those of the four⁃legged lattice⁃type high⁃bracket model.There are interactions between the bracket members,and solutions need to be proposed for the effects between the members under wind loads,and the influence of the spatial three⁃dimensional characteristics of the lattice⁃type high⁃bracket on the calculation results needs to be taken into account in the numerical simulation.This paper investigates the stability characteristics of lattice⁃type high⁃bracket against typhoons,which provides an important reference for improving the safety of bridge construction.