【作者】 苏成江；

【导师】 王秀丽；

【作者基本信息】 兰州理工大学 ， 结构工程， 2007， 硕士

【摘要】 在1994年的Northridge地震和1995年的Hyogo-ken地震中，中心支撑框架体系的房屋出现了大量的破坏，研究表明，产生这种破坏的原因是由于支撑过早屈曲使得承载力下降引起的。为了改善支撑的屈曲性能，使得在地震作用时，支撑不发生侧向屈曲，相对于传统中心支撑框架提出了一种新的可以避免支撑屈曲的体系，称为约束屈曲支撑框架体系。这种体系在美国和日本已经大量被采用，而且表现出了良好的抗震性能。本文首先应用ANSYS对支撑内核为“一”字矩形截面约束屈曲支撑在静力往复荷载作用下的受力性能进行模拟，通过计算得到支撑滞回曲线及其内部应力分布状况，追踪到了支撑内核高阶模态屈曲的过程，结果表明这种约束屈曲支撑具有良好的耗能特性。支撑内核与约束机构之间的缝隙和摩擦力是约束屈曲支撑的两个关键参数，通过对14个不同缝隙和5个不同摩擦系数的约束屈曲支撑的计算得出缝隙和摩擦力对约束屈曲支撑内力的影响，说明应确定合理的缝隙尽量减小摩擦力。其次对另一种质量较轻的双套管式约束屈曲支撑进行了有限元分析。结果表明这种支撑同样具有良好的滞回性能；结合各种非线性因素，考察了约束刚度比、初始缺陷对支撑极限承载力的影响，考察了约束刚度比对滞回性能的影响，提出保证支撑能正常工作而且经济的刚度比。最后将约束屈曲支撑应用于框架结构中，对普通支撑框架和约束屈曲支撑框架的滞回性能进行了对比，分析了二者的差异。采用弹塑性时程分析方法对约束屈曲支撑框架的抗震性能作了进一步的研究，通过对一个算例的分析验证了相对于普通中心支撑框架约束屈曲支撑框架具有更好的抗震性能。最后，通过改变约束屈曲支撑的布置方式，研究了约束屈曲支撑不同的布置方式对结构抗震性能的影响。更多还原

【Abstract】 In Northridge earthquake (1994) and Hyogo-ken earthquake (1995), a large amount of destruction appeared in the building of this kind of system. Studies have suggested, because of brace buckling early, the strength of sturucture was dropped. In order to improve the buckling performance of brace, make in earthquake occurrence, no buckling of brace will take place, as to traditional concentrically braced frame put forward a new system can avoid brace buckling, called buckling restrained braced frame. This system is a large amount of adopt already in Japen and U.S.A., demonstrates good anti-seismic performance.First, the bearing performance under horizontal low cycle loading of Buckling Restrained Brace with rectangle section core was analyzed used commercial software ANSYS. The distribution of internal forces of BRB were studied and high-order mode buckling process was tracked down. The results demonstrate a stable hysteretic behavior of brace. The influence on internal forces of gap between core steel-plate and exterior concrete as well as friction force of BRB were obtained through analysis. Fourteen models with different gaps and five models with different friction coefficient have been calculated. The results imperative that reasonable gaps should be confirmed and minish friction .Second, a new type doube tube BRB was analyzed. The analysis results also indicate, this kind of buckling restrained brace having good dissipation energy ability. Considered all kinds of nonlinearity, the influence of restraining ratio and initial imperfection on ultimate load, the influence of restraining ratio on hysteretic behavior of BRB were studied, a reasonable restraining ratio was suggested, with that restraining ratio BRB can work well and economically.On this basis, the further research of anti-seismic of buckling restrained braced frame was performed. Traditional braced frame and BRB braced frame were compared both in monotonic and cyclic loading. Example proved, as to concentrically braced frame, buckling restrained braced frame has better anti-seismic performance. Meanwhile, the study of impact on structural anti-seismic with different layouts of BRB was also performed.更多还原