地震作用下型钢混凝土异形柱框架动力特性及频谱反应分析  

Dynamic characteristics and spectrum response of SRC special-shaped column frame under seismic effect

作　　者：胡宗波[1,2] 薛建阳 HU Zong-bo;XUE Jian-yang(Postdoctoral Research Station of Civil Engineering College,Xi'an University of Architecture and Technology,Xi'an 710055,China;Institute of Equipment Management and Support,Engineering University of People's Armed Police Force,Xi'an 710086,China)

机构地区：[1]西安建筑科技大学土木工程学院博士后流动站,陕西西安710055 [2]武警工程大学装备管理与保障学院,陕西西安710086

出　　处：《振动工程学报》2021年第3期528-538,共11页Journal of Vibration Engineering

基　　金：中国博士后科学基金资助项目(2020M683432);国家自然科学基金资助项目(51308444);陕西自然科学基础研究基金资助项目(2014JQ7288)。

摘　　要：基于型钢混凝土(SRC)异形柱空间框架模型振动台试验,对模型结构的频谱特性、偏心动力反应、非线性反应规律进行了研究。结果表明:在三向地震作用下,模型结构在高阶振型中依次发生了Y向平扭和X向平扭耦合现象,振型形态依次为X向平动、Y向平扭、Z向振动、扭转、Y向平动;在强震作用下,模型X向、Y向、Z向和扭转自振频率分别下降31.02%,30.10%,39.72%和30.09%;模型结构的频响函数实部曲线的零点、虚部及幅值曲线的峰值点随着加载持时的增加逐渐向低频移动,结构损伤逐渐累积,刚度不断退化,动力刚度接近静刚度,结构的变形较大;通过数值分析可知,当偏心距一定、平扭周期比不变时,偏心结构的自振频率比、平扭耦联系数的峰值点相对于对称结构的峰值点明显推后;在强震作用下,偏心距小于0.1的模型结构的薄弱层出现在结构中下部,偏心距大于0.3的模型结构的薄弱层出现在结构上部;随着偏心距的增大,模型结构提前达到性能点,所有交点处的能力谱曲线未处于承载力明显下降段,结构抗震性能满足要求。Based on the shaking table test of SRC special-shaped column space frame model,the spectrum characteristics,eccentric dynamic response and nonlinear response law of the model structure are studied.The results show that,under the action of 3-dimensional seismic effect,the Y-direction and X-direction horizontal torsion coupling phenomena occur in the high-order vibration mode of the model structure,and the vibration modes are X-direction translation,Y-direction horizontal torsion,Z-direction vibration,torsion and Y-direction translation in turn;under the action of strong earthquake,the natural vibration frequencies of X-direction,Y-direction,Z-direction and torsion decrease by 31.02%,30.10%,39.72%and 30.09%respectively;the zero point,the imaginary part and the peak point of the real part curve of the frequency response function of the model structure gradually move to the low frequency with the increase of the load holding time,the structural damage gradually accumulates,the stiffness continuously degenerates,the dynamic stiffness is close to the static stiffness,and the structural deformation is great.Through the numerical analysis,it can be seen that when the eccentricity is certain and the horizontal torsion period ratio is constant,the peak points of natural frequency ratio and horizontal torsion coupling coefficient of eccentric structure is obviously pushed back compared with that of symmetrical structure;under the action of strong earthquake,the weak layer of the model structure with eccentricity less than 0.1 appears in the middle and lower part of the structure,and the weak layer of the model structure with eccentricity greater than 0.3 appears in the upper part of the structure;with the increase of eccentricity,the model structure reaches the performance point in advance,and the capacity spectrum curves at all intersections are not in the obvious decline section of bearing capacity.Therefore,the seismic performance of the structure meets the requirements.

关 键 词：型钢混凝土异形柱 框架结构 动力特性 频谱分析 非线性分析 

分 类 号：TU398.7[建筑科学—结构工程] TU311.3