剪切屈服型多耗能梁K形偏心支撑钢框架抗震性能研究

为了解决偏心支撑钢框架结构延性导致的地震作用取值偏大等问题,研究了剪切型多耗能梁偏心支撑结构的抗震性能。在试验模型的基础上,基于耗能梁腹板受剪面积基本不变的前提下,把耗能梁段的截面设计成多耗能梁模式,采用ABAQUS有限元软件建立了8个数值模型,分别进行单调加载和循环加载,分析了破坏模式、滞回曲线、承载力、刚度及耗能能力随耗能梁个数变化的情况。结果表明,耗能梁段塑性变形发展充分,有效保护了其他的非耗能构件;结构的承载力、屈服位移及耗能能力要好于单耗能梁模型;每个多耗能梁模型的初始刚度相差较小(4%以内),均小于单耗能梁模型,但多耗能梁模型能够延缓结构刚度的退化速率。所提模型能提高结构的抗震性能,对实际工程应用有一定的参考价值。

Study on seismic behavior of K-eccentrically braced steel structures with multi-shear links

To solve the problem of higher selected seismic effect value caused by the ductility of eccentrically braced steel structures, the seismic performance of the eccentrically braced structure with shear multi-links was studied. On the basis of the test model, the link cross section was designed into a multi-link model based on the constant shear area of the link web. Then eight multi-link numerical models were established by using ABAQUS finite element, and monotonic loading analysis and cyclic loading analysis were performed respectively. The changes of failure modes, hysteresis curve, bearing capacity, stiffness and energy dissipation capacity with the number of links were analyzed. The results show that the plastic deformation of the link is fully developed, which effectively protects other non-energy dissipation members; the bearing capacity, yield displacement and energy dissipation capacity of the structure are better than those of the single link mode; The difference in initial stiffness of each multi-links model is within 4%, which is smaller than that of single-link model, but the multi-link model can delay the degradation rate of stiffness. The proposed model can improve the seismic performance and has some reference for actual engineering application.