大跨网架屋面建筑结构的风致振动

Wind-induced vibration for long-span truss roof

依托某工程实例,通过风洞试验测得结构的风压系数时程,利用ANSYS参数化设计语言编制了能够精确求解大跨柔性网架屋面的风振系数及等效静风荷载的程序,将风压系数时程转化为相应的面荷载向量并加载至有限元模型,研究了大跨柔性网架屋面结构的风致振动.结果表明,60°、180°和270°为大跨网架面面结构的最不利风向角,应注意这几个风向角的抗风设计.大跨网架屋面的四周屋檐和两条相互垂直的中线,都是风致振动较大的位置,应采取抗风加固措施.

Based on one engineering example, a wind tunnel test was carried out to obtain the wind pressure time-history curves. And ANSYS parametric design language was also used to compile one program to calculate the wind-induced vibration coefficients and static wind equivalent load. Thus, wind pressure could be converted into area load that was applied in finite element analysis model to study wind-induced vibration of a long-span truss roof. The following conclusions have been obtained： 60°, 180° and 270° are the worst wind attack angles attention to which should be paid to in a wind-resistant design. Great wind-induced vibration mostly occurs in the cave and two perpendicular midcourt lines which should be reinforced.