正弦行波激励下单层偏心框架结构扭转响应的解析解

文中针对单层偏心框架结构,利用正弦行波激励研究了质量偏心率和激励频率对偏心框架结构行波扭转响应的影响规律.建立了行波激励下单层偏心框架结构的振动方程,采用相对运动法求解给出了正弦行波激励下单层偏心框架结构楼板的质心平动位移和转角位移以及楼板扭矩和柱剪力的解析解.计算了一个钢筋混凝凝土单层偏心框架结构的峰值楼板扭矩和峰值...

Analytical solutions for torsional response of single-story eccentric frame structure subjected to sinusoidal wave passage excitation

The influences of mass eccentricity ratio and excitation frequency on the torsional response of the single-story eccentric frame structure to sinusoidal wave passage excitation are studied in this paper.The dynamic equilibrium equation for the single-story eccentric frame subjected to wave passage excitation is established,and the relative motion method is used to solve the equation.The analytical solutions are respectively given for the mass center displacement and torsional displacement of the floor,and for floor torque and column shears with sinusoidal wave passage excitation.The peak floor torque and peak column shear of a single-story eccentric reinforced concrete frame are calculated,and the peak floor torque and peak column shear in terms of different eccentricity ratio and excitation frequency are analyzed.Studies show that there are resonance regions at two natural frequencies of structure for the peak floor torque of eccentric structure with wave passage excitation,there is only one resonance region at second natural frequency for symmetric structure.With the increase of eccentricity ratio,resonance regions of peak floor torque shift to low frequency and their ranges gradually increase.There exists a steep region at very low excitation frequency for the peak column shears in the excitation direction of both eccentric and symmetric structures subjected to wave passage excitation,and there are resonance regions at the two natural frequencies of structure.The position of the steep region is independent of eccentricity ratio,while the two resonance regions shift to low frequency with the increase of eccentricity ratio.Regardless of the eccentric or symmetric structure,when the excitation frequency is in a certain range below the fundamental frequency,the lower the excitation frequency,the more significant the wave passage effect on column shear.The peak column shears of columns near the center of mass are large,while the peak column shears of columns away from the center of mass are small for eccentric structure subjected to whatever wave passage excitation or uniform excitation.