中文摘要：

为了了解超高层建筑在地震作用下的非连续坍塌特征,以基于颗粒流理论的PFC3D作为模拟平台,模拟了某市内一拟建超高层建筑在地震作用下的坍塌过程。按照建筑物为核心筒-框架结构,且具有两变阶的特点构建模型,并分别施加了加速度a=0.2 g,0.3 g,0.4 g的正弦地震波,震动时间为9s,模拟时间为90 s。模拟结果表明：在a=0.2 g时,建筑物最终结构完整,符合7度抗震设计要求;a=0.3 g,0.4 g时,建筑物最终完全坍塌,其过程为：首先从核心筒中与震动方向相同的剪力墙开始破坏,然后是垂直震动方向的剪力墙折断,上部核心筒在整体完整情况下再次折断,下部框架分离,整体建筑垂直坍塌;a=0.4 g时的坍塌速度大约是a=0.3 g时坍塌速度的2倍。最后针对坍塌过程特征,提出了抗震构造措施。

英文摘要：

To understand the characteristics of discontinuous collapse of high-rise buildings induced by earthquake, based on the particle flow theory of PFC3D as the simulation platform, a high-rise buildings proposed to build in Shenyang was simulated for the process of collapse under action of earthquake. According to the frame-core tube structure and the characteristics of the two variable cross-sections, the building was modelled. The applied sine waves are accelerations with a = 0.2 g, 0.3 g and 0.4 g , vibration time is 9 s, simulation time is 90 s. Simula- tion results show that ： when a = 0.2 g, the final structure is intact, conform to the requirements of the 7 degree seismic design, when a = 0.3 g and 0.4 g, the building completely collapsed at last, The collapse process is as follows ： firstly, the shear wall of the core tube along the direction of vibration begin to damage, then the vertical vi- bration direction of the shear wall is broken;the upper complete part of the core tube is broken again, the lower frame separates, the whole building collapse vertically. When a = 0.4 g, the speed of the collapse is about 2 times of that for a = 0.3 g. Finally, seismic structural measures are put forward based on collapse process characteristics.