单层折面空间网格结构风荷载特性及等效静风荷载研究

对单层折面空间网格结构的表面风压分布和风振响应特性进行研究，采用荷载 响应相关法(LRC)与惯性力法计算结构的等效静风荷载，并分析了其计算精度，结果表明：在迎风面的体育场屋盖部分，气流在经过迎风面屋盖檐口后发生明显分离，形成漩涡，此处的平均负风压和脉动风压最大；整个屋面的绝大部分表面风压都表现为负压。增加肩谷环后，结构横向刚度提高较大，结构的1阶和2阶振型由原来的结构整体水平振动变为罩棚前端内环端部的局部竖向振动；在单层折面空间网格结构的风振响应中，参与结构振动振型较多，需要考虑多阶振型影响，且参与结构振动的主要为低阶振型；在脉动风荷载作用下各振型耦合作用较小；用LRC与惯性力法得到的单层折面空间网格结构等效静风荷载，计算精度可满足工程要求。

Wind load and equivalent static wind load of single-layer spatial reticulated structure

The single-layer spatial reticulated structure is a new kind of structure.The wind load distribution,vibration modes and wind-induced response are studied in this paper.While LRC and inertia force method could be used to calculate the static wind load of the single-layer spatial reticulated structure,the accuracy of this method was discussed.The following conclusion are drawn.Firstly,when the wind flow passes by the eaves of the roof,the flows separate from the roof and the vortex occurs.The negative mean wind and fluctuating load are the largest in this region;the mean wind pressure is mostly negative on the single-layer spatial reticulated structure.Secondly,after adding circumferential members at the shoulder valley in the structure,the horizontal structural stiffness is much increased,and the original whole horizontal vibration shapes of the first and second modes are turned into the local vertical vibration shape of the front ends of the inner circle.Thirdly,many modes have contribution on the structural wind-induced response,and higher modes should be considered;the mode coupling effect can be neglected.It is found that the equivalent static wind load got by LRC and inertia force method can ensure that the response of the single-layer spatial reticulated structure are correct.