半刚接钢框架的动力分析

推导了半刚接钢框架动力有限元的质量矩阵和刚度矩阵．建立了具有不同节点初始刚度的半刚接多层钢框架及相应刚性框架的计算模型．采用ANSYS软件进行数值模拟分析，研究了节点刚度对结构自振频率的影响以及结构在谐振荷载作用下的响应，对地震波激励下的结构进行了时程分析．分析结果表明不半刚接框架节点的柔性对结构自振频率产生较大的影响，节点柔性越大，结构自振频率降低也越大，结构的抗震设计应考虑节点柔性的影响；半刚接钢框架顶点位移和柱底剪力时程曲线在地震波激励时间内表现出良好的稳定性，柔性连接可以代替刚性节点用于抗震区的钢框架设计中．

DYNAMIC ANALYSIS OF STEEL FRAMES WITH SEMI-RIGID CONNECTIONS

Mass matrix and stiffness matrix of semi-rigid frames for dynamic finite element analysis are deduced . Multistory frames with semi-rigid connections of different initial stiffness are constructed together with the corresponding rigid frame. Finite element analysis software ANSYS is used to perform the numerical analysis. The influence of connection stiffness on natural frequencies of structures is analyzed. The response of different frames according to harmonic loading with different frequencies is studied. Further, by adopting a time-dependent method, structures under excitation of seismic waves are analyzed. Analysis results show that the connection flexibility has a great effect on structure's natural frequencies. The natural frequency decreases with the increase of connection flexibility. It is necessary to consider the connection flexibility in the seismic design of steel structures. Time curves of top point lateral displacement and column base shearing force of semi-rigid frames behave stably during the excitation time. Flexible connections can be used instead of rigid connections in seismic design of steel frames.