为了避免抗震设计规范中定性条文的不确定性限制而合理评价复杂型式高层结构整体抗震性能,通过建立大规模三维有限元数值模型和采用Newrnark逐步积分方法求解考虑几何非线性大变形的动力平衡方程,并将时程分析法与振型分解反应谱法进行对比分析。计算分析表明:三组地震波输入计算所得的结构各自底部剪力、平均底部剪力与基底剪重比均满足规范限值要求;从变形和内力结果上看,结构两水平方向侧向刚度差异较明显;时程内两水平向层间位移角平均最大幅值亦满足规范限值要求,但结构型式空间布局变化较大,结构沿高度存在多处刚度转换层,层间位移角发生多处突变;另外,结构局部区域竖向构件侧向转角超出规范线性层间位移角限值,结构局部可能会存在应力集中现象,在工程设计中应予以考虑。
Abstract: For the aim to avoid the limitation of the qualitative items of the Code for seismic de- sign of buildings and reasonably evaluate the dynamic properties of high-rise buildings, dynamic e- quilibrium equations considering geometric nonlinearity and large deformation are solved by using Newmark step-by-step integration method based on three-dimensional finite element model, and comparative analysis with the results of spectrum response is conducted as well. Computational analysis reveals that the maximum values of respective base shear, mean base shear and mean shear-gravity ratios under the inputs of three seismic waves are within the allowed values of the Code demands; it is indicated from the results of internal forces and displacements that the differ- ence between the two translational stiffness in two horizontal directions is obvious; furthermore, though computed mean maximum values of inter-story drifts in time domain meet the requirement of the Code, there are visible extreme points where sudden change of inter-story drifts occurs and the counterpart angels of rotation in local area of structure are excessive, which should be empha- sized in engineering design.