Theoretical and Experimental Study of Nonlinear Dynamic Behaviors of Spatial Structures

本研究从理论和实验两个方面对空间结构的非线性动力特性进行了研究。(1)在第（1）项中，利用对几何非线性运动方程进行数值积分得到的时间历程，数值地研究了结构形状如矢跨比、阻尼和激励类型对动力屈曲荷载的影响。动力屈曲载荷由Budiansky-Roth准则估计。第（2）项提出了用广义逆理论对动不定框架进行动力分析的数值方法。动不定框架包括索结构、膜结构、可移动结构如可折叠结构、空间结构等，属于“不稳定结构体系”。“本方法可以有效地应用于分析这些结构的动力特性。通过数值计算结果与实验结果的比较，验证了该方法的有效性。

In the research study, the following two items about nonlinear dynamic behaviors of spatial structures were investigated from the theoretical and experimental view points.(1) Dynamic Buckling of Shallow Structures under the Up-and Down Excitation(2) Dynamic Behaviors of Kinematically IndeterminateIn item (1), the effects of shape of structure such as rise-to-span ratio, damping and type of excitation on the dynamic buckling load are numerically examined by using time histories which are obtained by the numerical integration for the geometrically nonlinear equations of motion. Dynamic buckling loads are estimated by the Budiansky-Roth criterion. Frequency-dependent characteristics of dynamic buckling load is shown.In item (2), a numerical method using the generalized inverse theory for the dynamic analysis of kinematically indeterminate framework was presented. Kinematically indeterminate frame includes cable structures, membrane structures, movable structures such as foldable structures, space structures, etc., and is classified into 'Unstable Structural System." The present method can be effectively applied to analyze the dynamic behaviors of these structures. The validity of the present method is examined by comparing numerical results with the experimental results.