地震荷载下镂空高层建筑坍塌形式及时间分析

为研究镂空建筑在不同峰值加速度的地震荷载影响下产生的坍塌破坏,分析坍塌破坏形式和经历时间,基于颗粒流理论构建模型并实施模拟。所研究建筑结构形式为两栋具有核心筒建筑组成的镂空构造,上部有连桥相连。地震荷载是峰值加速度a分别为0.2g、0.3g和0.4g的正弦波,作用时间为9 s。对该建筑施加上述3种地震荷载,模拟分析坍塌形式和历经时间。结果表明,a=0.2g时,建筑开始坐塌、倾斜及连桥破坏的时间接近,整个坍塌过程经历时间最长。相比之下a=0.3g,a=0.4g时,坐塌要快得多、倾倒和连桥破坏延迟。比较a=0.3g和a=0.4g,后者的连桥破坏、倾斜和坐塌经历时间明显小于前者。因此峰值加速度的线性增加,不一定导致各参量时间同向线性变化,这可能是建筑结构形式造成的。

Analysis of the collapse form and process of the hollow-out high-rise buildings under the earthquake shaking load

The present paper is engaged in an analysis of the collapse form and the process of the hollow-out high-rise buildings under the earthquake shaking load in hoping to pursue and trace the destruction process and determine the collapse experiencing time based on the particle flow theory.As is known,the building under the strong earthquake shaking load has to experience different violent unexpected accelerations.Under the above conditions,it would be possible for us to work out a simulation model,in which the building structure form tends to be hollow out with two construction core tubes.Let' s taken the two aforementioned buildings for example,they are of 72 stories 216 m high in a street section of 20 m × 30 m square.What is more,they are linked together by the bridge-form corridor at their tops.The core tubes of the two buildings are rectangular in a reinforced concrete cylinder with a section being 10 m × 20 m.The thickness of the side wall is 1 m high at the bottom of the core tube throughout the entire building.Whereas the framework extends 5 m in each side from the core barrel,the load-bearing column and beam are 1 m × 1 m.On the one hand,the peak acceleration a of the earthquake load is supposed to be 0.2g,0.3g and O.4g,respectively,on the other,the wave form is sine with the duration being 9s.With the above three kinds of earthquake load in mind,we have simulated and analyzed the collapse form likely for the building to take and the collapse time length for it to experience in the folowing way:with a =0.2g,the process of the collapse to be experienced for the construction tend to occur in the following procedure:beginning to collapse and tilt,with the bridge damage closed,while the entire collapse process may last the longest time.Compare and contrast a =0.3g and a =0.4g to a =0.2g,the top-down collapse may tend to come up much faster,with the dumping and the bridge damage being delayed.Therefore,comparing a =0.3g and a =0.4g,the bridge damage,tilting,and,then,decompose and downward collapse of the latter may happen to be significantly slower than the former.Therefore,the peak acceleration of the linear damage increase does not necessarily lead to the change in time with the synthetic linear,which may be caused by the building structure form itself.