18层框-筒结构楼房拆除爆破数值模拟分析

Demolition blasting and numerical simulation analysis of 18 storey frame-barrel structure building

对于复杂环境条件下大跨距高楼房爆破拆除工况,在综合考虑周边环境条件的基础上,为保障楼房顺利倒塌,拟采用折叠爆破,分区块延时起爆方式,同时采用控制爆破技术减小楼体触地塌落振动对于周围建筑的危害。为验证爆破拆除设计的合理性,采用ANSYS/LSDYNA数值仿真软件建立楼体分离式共节点三维有限元模型,对楼体倒塌形态进行预分析,通过分析楼体顶部关键节点位移变化趋势,发现楼房按原定设计方向倒塌,现场爆破后楼房解体充分,爆破后爆堆堆积,未出现明显楼体部件飞散等问题。研究结果表明:大跨距楼房重力势能转换较快,采用折叠爆破结合切梁断柱法可有效保障楼房迅速解体,降低触地冲量,减小触地振动等有害效应,采用分离式共节点竖直模拟方式可有效预测楼体爆破倒塌运动趋势,为类似爆破工程提供参考。

For the blasting demolition of long-span and high-rise buildings under complex environmental conditions,considering the surrounding environmental conditions,it is planned to adopt folding blasting and block delay blasting to ensure the smooth collapse of buildings,and at the same time,the controlled blasting technology is adopted to reduce the harm of building collapse vibration to surrounding buildings.In order to verify the rationality of blasting demolition design,ANSYS/LSDYNA numerical simulation software was used to establish a three-dimensional finite element model with separated common nodes of the building,and the collapse form of the building was pre-analyzed.By analyzing the displacement change trend of the key nodes at the top of the building,it was found that the building collapsed in the original design direction,the building was fully disintegrated after on-site blasting,and the blasting piles piled up after blasting,and there were no obvious problems such as the scattered parts of the building.The research results show that the gravity potential energy of long-span buildings can be transformed quickly,and the method of folding blasting combined with beam-cutting and column-breaking can effectively ensure the rapid disintegration of buildings,reduce the impact on the ground and reduce the harmful effects such as vibration on the ground.The vertical simulation method of separated common nodes can effectively predict the blasting collapse movement trend of buildings,which can provide reference for similar blasting projects.