体内张拉成形空间网格结构自振特性研究

Research on Free Vibration Characteristics of Internal-Prestressed Reticulated Space Structure

体内张拉成形空间网格结构是由上弦梁、下弦(下弦管内穿索)、腹杆以及环杆等构件组成的一种新型空间结构形式,是通过对下弦管内索施加预应力张拉成形,进而改善结构受力性能的自平衡体系。文章利用ANSYS软件中的子空间迭代法,分析了体内张拉成形空间网格结构的自振特性,并针对不同的参数如矢跨比、立柱高度、预应力大小、腹杆数量以及环杆数量进行了参数分析,得出了各参数对结构的自振特性的影响。

Intemal-prestressed reticulated space structure is a novel prestressed long span structure, which is composed of upper chord, lower chord, web member and lateral support member. The erection of this structure into its final configuration is achieved by tensioning prestressing cables passing through the lower chord, which can improve its mechanical characteristics. The free vibration characteristics of this structure are analyzed in this paper by ANSYS with the method of subspace iteration. Through analysis of the different parameters, such as rise-span ratio, height of column, prestress, number of the web member and lateral support member, the influence of these parameters on the free vibration characteristics as well as the pattern of free vibration were obtained.