框架结构局部柱铰整体屈服机制的控制

Discussion on a global yield mechanism with local column plastic hinge in moment-resistant frame structure

框架结构局部柱铰整体屈服机制允许中柱的柱端和边柱的梁端屈服,要求边柱强度更高以避免发生层间破坏。该屈服机制的强柱弱梁条件不在于使每个节点都满足强柱弱梁的条件,而从结构整体出发要求满足基于层间柱梁强度比的强柱弱梁条件,使节点的强柱弱梁条件得以放松。基于梁铰屈服机制和部分柱铰屈服机制分别设计2组6层框架结构,利用ABAQUS有限元分析软件建立实体模型,采用Pushover方法进行推覆分析,对比不同屈服机制的层间位移角响应及构件塑性铰分布响应。结果表明,层间柱梁强度比对屈服机制的形成有重要影响,具有部分柱铰的框架结构在地震作用下的安全性不低于只允许出现梁铰的框架结构。

This paper presents a new global yield mechanism frame where some columns yield,based on the conception of column-to-beam strength ratio in a story. In a frame,the exterior columns are designed stronger to avoid story failure mechanism,while the interior columns are allowed to yield. Thus,the interior columns can not obey the principle of strong column and weak beam strictly in codes. Based on beam yield hinge mechanism and hybrid yield mechanisms two six-story frame structures were designed,a solid models were built using ABAQUS software. Pushover analysis was performed to compare the similarities and differences about the inter-story drift angle and distribution of plastic hinges. The results indicate that column-to-beam strength ratio in a story is an effective parameter to control yield mechanism of the structure,and the safety of moment-resistant frame with hybrid yield mechanism is not less than that of a frame with beams yield mechanism.