【作者】 赵林；

【导师】 陈向荣；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2011， 硕士

【摘要】 屈曲约束支撑(Buckling-Restrained Braces)是一种新型耗能构件,它解决了普通支撑经常失稳和刚度突然下降的弊端,其在拉压状态下均能屈服而不屈曲并且在屈服后能够提高结构阻尼耗散输入到结构的地震能量。目前屈曲约束支撑应用较为广泛,在日本、美国、加拿大、我国台湾地区及大陆都有较好应用。首先对屈曲约束支撑的作用机理,屈曲约束支撑的有效约束比及芯材与外套管之间的间隙进行理论分析,并取不同间隙的构件进行有限元分析。其次分别选取不同的刚度比进行屈曲约束支撑钢框架的设计。利用ANSYS有限元软件对10层单榀屈曲约束支撑钢框架进行弹塑性时程分析。比较不同刚度比下结构的底部剪力、顶层加速度及顶层位移,并建立其在地震作用下的最大层间位移角随抗侧刚度比变化的关系曲线及不同刚度比下最大层间位移角分布均匀程度的关系曲线。最终提出屈曲约束支撑和钢框架刚度比的合理取值范围,为屈曲约束支撑框架的设计提供依据。再者利用有限元软件SAP2000对合理刚度比的屈曲约束支撑框架进行静力弹塑性分析。考虑高阶振型影响求解能力谱曲线并引进不同的位移延性系数绘制需求谱曲线,然后将两者曲线绘制在同一坐标系求解性能点。初步探讨了合理刚度比下屈曲约束支撑钢框架的结构影响系数及位移放大系数。最后,为了比较不同屈曲约束支撑布置形式对屈曲约束支撑钢框架的抗震性能影响,本文设计出4种不同布置形式的屈曲约束支撑钢框架,分别采取底部剪力法、振型分解反应谱法、动力时程分析、静力弹塑性的分析方法对其进行抗震性能分析,为屈曲约束支撑设计提供依据。更多还原

【Abstract】 Buckling Restrained Braceds (BRBs) now are new type of energy dissipation components.They can solve the problem that the lateral stiffness of ordinary braces falls suddenly under instability. In the state of tension and compression, the BRBs not only can yield, but also can improve the structure damping which dissipates the seismic energy of the structure under the state of yield. Recently, BRBs are used popularly, which have been used in Japan, the US, Taiwan and China.Firstly, the theory analysis is conducted to the mechanism of BRBs, the restraint stiffness ratio of BRBs, and the gap between the buckling-restraining unit and core segment. And the BRBs with different gaps are analysised by finite element software.Secondly, the BRBFs are designed according to the different rigidity ratios. Nonlinear time history analysis is conducted to10-story plane BRBFs by finite element software AYSYS. And the base shears, top floor accelerations and top floor displacements are compared under different rigidity ratios. The relationships of maximum story drift ratios and the uniformity of maximum story drift ratios with different rigidity ratios are established. At last a reasonable range of rigidity ratio is recommended, which is the reference for the design of BRBFs.Furthermore, nonlinear static analysis is conducted to the BRBFs under reasonable rigidity ratio by finite element software SAP2000. The influence of high-order modes are considered when solving the capacity spectrum curve. And the demand spectrum curves are drawn under different displacement ductilities. Then, the two curves are drawn in the same coordinate system to solve performance point.The response modification factor and the displacement amplification factor of BRBFs are discussed under reasonable rigidity ratio.Finally, to comparing seismic behaviors under the different layout of BRBs, four types of the structure models are designed. The bottom of the shear method, response spectrum method, linear time history analysis, nonlinear time history analysis and pushover analysis are conducted to the structure models, and seismic behaviors under the different layout of BRBs are compared, which are the reference for the design of BRBFs.更多还原