防屈曲支撑在超限高层钢—砼混合结构中减震效果分析

防屈曲支撑分耗能型和承载型,在地震工况作用下是否启动耗能是区分两种类型的重要标准,防屈曲支撑耗能启动承载力是决定其耗能能力的关键因素.通过对某一高层实际工程,用有限元软件来分析防屈曲支撑结构在地震作用下的反应,依据多遇地震下支撑的弹性内力来设计防屈曲支撑在地震作用下耗能启动承载力,采用EL-Centro波、Taft波、人工波3条地震波,用时程分析方法在小震、中震及大震工况作用下来分析防屈曲结构的减震耗能能力.结果表明:在小震下支撑保持弹性不启动耗能,仅对结构提供刚度;在中震下支撑屈服后耗能开始启动,消耗地震能量,有效保护了主体结构;在大震作用下耗能支撑和结构主体共同作用,保护主体结构不倒塌.

Analysis of Damping Effect of Buckling Restraining Brace in Super High-rise Steel-concrete Hybrid Structures

The buckling restraining brace has two kinds：load bearing brace and energy dissipation brace. Whether the damper starts working subjected to seismic action is an important standard to distinguish the two. Energy start bearing capacity is the key to decide its energy dissipation. By a finite element analysis software to BRB-Structure,based on elastic internal forces of the brace under the frequent earthquakes,the bearing capacity of energy dissipation brace under the action of earthquakes is designed. Three seismic waves （EI.-centro,Taft and artificial wave） and time history analysis method are used in working condi tions of small, moderate and major earthquakes to analyze the energy dissipation. The results show that, BRB keeps elastic and it provides the structure enough stiffness under small earthquakes~it can start to dissipate the energy under moderate earthquakes and so protect the main structure effectively. With the energy dissipation brace and the main structure working together, it can protect the main structure from collapsing.