脊谷式张拉膜结构风振特性分析

Wind-induced response analysis of wave-shaped membrane structures

张拉式膜结构属风敏感体系,对其在脉动风荷载作用下的动力性能进行准确评估一直是该类结构设计中的重要内容.但国内以往在这方面的研究较少,该问题一直没有很好地解决.本文采用非线性随机模拟时程分析方法对张拉式膜结构的典型形式之一——脊谷式膜结构的风振响应特性进行系统的参数分析,探讨了来流特性、跨度、高跨比、膜预张力等参数对结构动力性能的影响.在此基础上,本文提出了一种针对于张拉膜结构特点的抗风设计方法.

Wave-shaped membrane structures are a typical kind of tensile membrane structures. In the past, most researches are focused on their static performance and few on dynamic performance. In this paper, the systematic parameter analysis of wind-induced response of wave-shaped membrane structures is presented with nonlinear random simulation method in time domain, and the effects of span, rise-span ratio, prestress of membrane, characteristic of the wind flow on dynamic performance are considered. Moreover, a statistical method of dynamic coefficient for the whole structure is proposed. With this method, dynamic coefficients of displacements and internal forces are analyzed,which include dynamic coefficients of displacements and internal forces of the membrane and the cable, and that of the reaction force. Finally, a formula of dynamic coefficient is proposed,which would have some reference to the design of wave-shaped membrane structures.