K型偏心支撑钢框架在循环荷载作用下的滞回性能分析

K型偏心支撑钢框架是偏心支撑结构中常用的一种抗震耗能结构形式,偏心支撑结构弹性阶段刚度大,塑性阶段耗能能力强是适用于高烈度震区的一种有效的抗侧力结构体系.根据偏心支撑结构在地震荷载作用下耗能梁段进入塑性的破坏特点,提出了耗能梁段采用曲壳单元和其余构件采用梁单元的非线性有限元模型来分析K型偏心支撑钢框架在循环荷载作用下的滞回性能和破坏机理,并自编了计算程序.通过有限元模拟计算分析,得到了K型偏心支撑钢框架抗震设计中合理的支撑截面大小、耗能梁段长度、高跨比、加劲肋间距、加劲肋厚度、腹板厚度等设计参数的确定方法.

Energy-dissipation of K-Type eccentrically braced steel frame under cyclic loading

Eccentrically-braced steel frames provide high elastic stiffness and demoustrate excellent energy dissipation capacity,making a lateral load-resisting sqstem applied to the high intensity area.In the light of the fact that eccenfrically-braced steel frames collapse after the link beams go into plastic deformation under earthquake loading,a new analytical model with the sheel element applied to link the beams with large deformation and plastic deformation and with the beams element applied to the other parts of the structure is presented in this paper for analyzing the energy dissipation behavior and collapsing mechanisms of this K-type eccentrically-braced frames.Computer program is compiled and a nonlinear finite element program is applied to analyge the behavior of this K-type eccentrisally-braced steel frame under cyclic loading.Through the me thod the design of brace stiffness linking with the length,high-span ratio,thickness of flange,as well as with the distance and thickness of the links rib is achieved.