何曉寒
摘 要:為了研究鋼框架結(jié)構(gòu)在增設(shè)屈曲約束支撐后的減震性能,本文以某高烈度地區(qū)鋼框架結(jié)構(gòu)為研究對象,并通過有限元軟件SAP2000,分別對純鋼框架結(jié)構(gòu)和加屈曲約束支撐的減震結(jié)構(gòu)進行了模擬,并按規(guī)范要求選取了三條地震波,對其進行了動力特性分析以及動力響應分析。在動力特性分析中,通過對比兩種結(jié)構(gòu)的前三階主振型,確定其平扭屬性,發(fā)現(xiàn)其都滿足規(guī)范要求,但增設(shè)屈曲約束支撐后,減震結(jié)構(gòu)的抗側(cè)剛度明顯提高。在動力響應分析中,分別用反應譜法以及非線性時程分析法求解了兩種結(jié)構(gòu)的層間位移和層間位移角,發(fā)現(xiàn)加屈曲約束支撐的減震結(jié)構(gòu)的層間位移角與層間位移都明顯小于純鋼框架結(jié)構(gòu),減震效果明顯。
關(guān)鍵詞:減震;屈曲約束支撐;鋼結(jié)構(gòu)
中圖分類號:TU352.11 ? ? 文獻標識碼:A? ? 文章編號:1003-5168(2021)21-0049-03
Analysis of the Shock Absorption Performance of Steel Structure Based on SAP2000
HE Xiaohan
(School of Civil Engineering and Communication, North China University of Water Resources and Electric Power, Zhengzhou Henan 450045)
Abstract: In order to study the shock absorption performance of steel frame structure with buckling restrained brace. In this paper, the steel frame structure in a high seismic intensity area is taken as the research object. Through the finite element software SAP2000, the pure steel frame structure and the damping structure with buckling restrained brace were simulated, and three seismic waves are selected according to the requirements of the code, the dynamic characteristic analysis and dynamic response analysis are carried out. In the analysis of dynamic characteristics, by comparing the first three main modal of the two structures, the flat torsion properties are determined, and it is found that both of them meet the requirements of the code, but the lateral stiffness of the damping structure is significantly improved after adding buckling restrained brace. In the dynamic response analysis, the inter-story displacement and inter-story displacement angles of the two structures respectively solved by response spectrum method and non-linear time history analysis method. Meanwhile, it found that the inter-story displacement angle and inter-story displacement of the damping structure with buckling restraint brace are significantly smaller than that of the pure steel frame structure, and the damping effect is obvious.
Keywords: shock absorption; buckling restrained brace; steel frame structure
隨著社會經(jīng)濟的快速發(fā)展,我國人口越來越多。為了節(jié)約土地,增加住房和居住人口,我國高層鋼框架結(jié)構(gòu)住宅迅猛發(fā)展。我國是地震多發(fā)國家,地震是最大的災害之一,對人民的生命財產(chǎn)危害重大。為了減輕地震災害的影響,大量減震裝置因此產(chǎn)生,比如屈曲約束支撐[1],屈曲約束支撐又稱為防屈曲約束支撐(簡稱BRB)。有學者通過SAP2000有限元軟件分析了加屈曲約束支撐結(jié)構(gòu)的減震性能[2]。為進一步對純鋼框架結(jié)構(gòu)和增設(shè)BRB的減震結(jié)構(gòu)的減震性能進行對比分析[4],本文分別建立了不加支撐的純鋼框架結(jié)構(gòu)和增設(shè)BRB[3]的減震結(jié)構(gòu)的有限元模型,求解了其動力特性以及動力響應,并進行了對比分析。
1 工程概況
本文研究對象的工程概況如下:該建筑采用鋼框架結(jié)構(gòu)體系,地上八層,見圖1。該建筑設(shè)計使用年限為50年,抗震設(shè)防烈度是8度,設(shè)計基本地震加速度是0.2 g,建筑場地類別為Ⅲ類,特征周期為0.45 s,地震峰值加速度為0.3 g。