橡胶支座与柱串联体系的动力特性分析  

Dynamic characteristics of a system of rubber bearings serially connected with columns

作　　者：杜永峰[1,2] 林治丹[1] 李慧[2] 

机构地区：[1]兰州理工大学防震减灾研究所,兰州730050 [2]兰州理工大学西部土木工程防灾减灾教育部工程研究中心,兰州730050

出　　处：《振动与冲击》2012年第17期134-139,共6页Journal of Vibration and Shock

基　　金：国家自然科学基金(50778087);国家自然科学基金(50978130);甘肃省科技支撑项目资助(090-GKCA040)

摘　　要：针对工程界比较关注的橡胶隔震支座与柱串联的隔震体系,研究了串联隔震体系横向振动的固有频率,探讨了轴向压力和不同隔震支座等效弯曲刚度对串联隔震系统固有频率的影响。考虑横截面转动和剪切变形以及轴向压力的影响,建立了串联隔震系统横向自由振动的数学模型;采用微分求积单元法(DQEM)对所得控制方程和边界条件进行离散处理,避免了繁琐的偏微分方程求解;数值求解固支—自由边界条件下串联隔震体系的横向固有频率,并得到该系统横向固有频率参数随压力变化的曲线。数值结果表明:轴向力的增加将显著降低串联隔震系统的低阶固有频率;在总高度一定的情况下,隔震支座尺寸的增大对串联隔震体系的力学特性也有显著的影响。Aiming at a system of rubber bearings serially connected with columns, its natural frequencies were investigated, and the effects of axial load and different rubber bearings were discussed. Taking the effects of cross-section rotatry, shear distortion and compression axial force into account, the mathematical model for free vibration of the system was established. The differential quadrature method was employed for diseretizing the governing equations and the boundary conditions. The natural frequencies of the system with clamped-free boundary conditions were solved numerically, and the curves of natural frequencies versus compression axial force were presented. It was shown that increase in axial force reduces the lower order natural frequencies significantly, and in cases of the unchanged total height, decrease in the equivalent bending stiffness of rubber bearings reduces the natural frequencies to a certain level.

关 键 词：橡胶隔震支座—柱串联隔震体系 微分求积法 固有频率 横向振动 

分 类 号：TU352.1[建筑科学—结构工程]