椭圆形平面预应力索网大变形非线性自由振动研究  

Large Deformation Viberation Frequency of Elliptic Plane Prestresed Cable-net with Geometrically Nonlinearity

作　　者：尚仁杰[1] 李谦[1] 吴转琴[1] 李佩勋[1] 刘景亮[1] 

机构地区：[1]中冶集团建筑研究总院,北京100088

出　　处：《应用力学学报》2008年第3期484-488,共5页Chinese Journal of Applied Mechanics

摘　　要：对椭圆形边界的平面索网结构自由振动的主频率进行了研究,考虑索网结构大变形产生的几何非线性项的影响,用最小势能原理推导了非线性振动的微分方程,研究了线性振动频率、大振幅振动频率和大变形后小振幅的振动频率计算方法,并对3个频率进行了比较分析。As the plane cable-net with small rigidity large deformation is subject to side wind load, it is necessary to consider the large deformation effects. The frequency of elliptic plane cable-net under the large deformation is evaluated, the vibration equation of the prestressed elliptic cable-net is deduced with variational principle method considering the influence of geometrically nonlinearity. Under three frequencies, five different amplitude with the maximum deformation up to 0.2m, 0.4m, 0.6m, 0.8m, and 1.0m are compared. It can be seen that when the deformation gets 0.6m , the vibration with large deformation corresponds to f=0.898Hz,about 25% higher than the linear computation frequency f=0.719Hz; The vibration frequency with small deformation near 0.6m, f=1.275Hz,about 77% higher than the vibration frequency for the position without deformation. Therefore for the structure of plane pre-stress cable-net, the influence of non linearity with large deformation on the vibration should not be ignored.

关 键 词：平面索网 椭圆形 大变形 非线性 振动 

分 类 号：TU312[建筑科学—结构工程]