摘要
关键单元指其破坏将导致结构整体倒塌的单元,确定关键单元是结构设计及维护中的重要问题.为了寻找杆系结构中的关键单元,采用摄动理论中整体刚度矩阵的相对条件数衡量结构的整体性;定义杆件局部范围,并采用局部应变能大小考察单根杆件初始破坏对整体结构倒塌的中间传递.算例分析表明,整体和局部判定方法的结果基本相符,但用整体判断方法,一些杆件对整体倒塌并不重要,而局部应变能判断方法,这些杆件将可能传递倒塌.整体刚度矩阵相对条件数的整体判定方法,可能出现关键单元的伪判定,解决途径是将初始破坏从单一杆件扩展到结构组成模块.网架结构算例表明,模块越接近支座,其重要性越高,边部模块比中间模块更加重要.
The key elements are defined as elements those damages will lead to overall collapse of structure. It is one of crucial issues to determine key elements for the structural design and maintenance. In order to determine key elements in member structures, the relative condition number in perturbation theory was employed for appraisal of integrity of the structures. Local region for a certain member in structures was defined, and, the magnitude of local strain energy was utilized to investigate the collapse relay from initial failure of single member to overall collapse of structure. The case studies manifest that the results from global and local methods are basically identical with each other. However, a few members were found by the global judgement method less important contribution to the overall collapse as well as they might greatly relay collapse from the local energy judgment method. Fraud judgement of key elements could happen in the global judgment method by relative condition number of the whole rigid matrix. The effective approach to the fraud judgment cracking is to extend initial failure from single member to structural configuration module. The case study of a latticed structure shows that the higher importance the structural configuration modules have, the closer they are to support, and the sideward modules have higher importance than those in interior regions.
出处
《空间结构》
CSCD
北大核心
2014年第1期58-63,共6页
Spatial Structures
关键词
杆系结构
关键单元
局部应变能相对条件数
关键模块
member structure local strain energy
key elements
Relative Condition Number
the key module.
