Initial postbuckling behavior of thin-walled frames under mode interaction
Initial postbuckling behavior of thin-walled frames under mode interaction
复制标题
模式相互作用下薄壁框架的初始后屈曲行为
DOI：
10.1016/j.tws.2013.03.004
复制
发表时间：
2013
影响因子：
6.4
通讯作者：
S. Gabriele
中科院分区：
文献类型：
--
作者：
N. Rizzi;V. Varano;S. Gabriele
由具有槽形横截面的梁和柱组成的L形框架，已经由两位作者[14]在先前的工作中进行了分析。根据纵横比和节点配置，已经证明，结构可以同时表现出两种屈曲模式。本文利用考虑模态相互作用的弹性分叉渐近理论，确定了分叉路径的初始斜率。已经考虑了焊接连接中更常用的接头配置的三种情况。对于每种情况，都发现了三条可容许的分叉路径，其中两条的斜率与无模相互作用时的斜率具有相同的数量级，而另一条的斜率最大。选择，对于每个联合的情况下，分叉的路径具有较高的斜率和它们之间的最小的一个，它被发现，它是相关联的分叉在较高的临界载荷的路径。这意味着更硬的结构也是更少的缺陷敏感性。最后，对于每一个研究的情况下，初始缺陷的影响已被考虑和框架的真实的承载能力已被确定。最后将计算结果与有限元软件ABAQUS的计算结果进行了比较。
An L frame made up by beam and column having channel cross sections, has been analyzed in a previous work by two of the authors [14]. Depending on the aspect ratio and the joint configuration, it has been proved that the structure can exhibit two simultaneous buckling modes. Here using the asymptotic theory of elastic bifurcation that takes into account mode interaction, the initial slope of the bifurcated paths has been determined. Three cases of joint configurations, which are the more common used in welded connections, have been considered. For each case three admissible bifurcated paths have been found. Two of them show a slope having the same order of magnitude of the ones found in the absence of mode interaction while the remaining exhibits a slope largely steepest. Selecting, for each joint case, the bifurcated path with the higher slope and between them the smallest one, it is found that it is associated to the path which bifurcates at the higher critical load. This means that the stiffer structure is also the less imperfection sensitive. Finally for each one of the cases studied, the effect of initial imperfection has been considered and the real load carrying capacity of the frames has been determined. Finally some results have been compared with those obtained using the FE code ABAQUS.