基于几何稳定性的攀达穹顶顶升杆布置方法  

A method for analyzing layout of jacking struts of Pantadome based on geometric stability

作　　者：王玮[1] 邓华[1] WANG Wei;DKNG Hua(The Spare Slrurturrs Research Center,Zhejiang Univrrsity,Hangzhou 310058,China)

机构地区：[1]浙江大学空间结构研究中心

出　　处：《建筑结构学报》2020年第2期107-114,共8页Journal of Building Structures

摘　　要：基于机构协调条件,给出了攀达穹顶从安装面到设计构型作最短距离运动的刚体位移方向求解方法。进行正交变化,将求得的刚体位移方向转化为系统机构位移模态矩阵的主向量。以驱动系统沿刚体位移方向运动,同时以保证系统维持足够的几何稳定性为目标,讨论顶升杆的布置问题。数学上将顶升杆的增加描述为对攀达穹顶所有机构位移模态对应的零特征值的正扰动。对应于攀达穹顶的刚体位移方向(主机构位移模态向量),由节点下方设置的顶升杆对其特征值的扰动最大确定该顶升杆的方向。对比扰动量的大小,可定量评价在不同节点设置顶升杆的优劣。对刚体运动路径上较多的代表性构型开展相同的分析,可确定布置顶升杆的最佳节点区域。针对一个双层网格攀达穹顶算例进行计算,以上策略能够有效得出该算例的顶升杆布置方式。Based on the compatibility relationship of mechanism,a method was developed to determine the direction of rigid-body motion along the shortest path between the assembly surface and the design configuration of Pantadome.By orthogonal transformation,the obtained direction of rigid-body motion was converted into the main vector in the matrix of mechanism displacement modes.The issue on the layout of jacking struts was investigated to ensure that the Pantadome is driven to move in this direction of rigid-body motion,and also to maintain the system with sufficient geometric stability.Mathematically,the introduction of jacking strut was described as the positive perturbation to the zero eigenvalues for all modes of mechanism displacement of the Pantadome.Corresponding to the direction of rigidbody motion(the main vector of mechanism displacement modes),the direction of jacking strut connected with a certain joint in the Pantadome can be determined by maximizing the perturbation.By comparing the magnitudes of perturbation,the quality of setting jacking strut under different joints can be evaluated quantitatively.When the same analysis was also carried out for more selected configurations on the path of rigid-body motion of the Pantadome,the optimal joint areas could be determined for the layout of jacking struts.A double-layer reticulated Pantadome was employed as the illustrative example,and the method put forward in this paper could figure out the layout of the jacking struts for this Pantadome.

关 键 词：攀达穹顶 顶升杆布置 刚体运动 几何稳定 特征值扰动 

分 类 号：TU323.4[建筑科学—结构工程] TU311.2