建筑结构学报2024，Vol.45Issue(1)：12-26,15.DOI:10.14006/j.jzjgxb.2023.0048
近距离爆炸作用下工字形截面钢柱荷载分布与动态响应数值模拟研究
Numerical investigations of blast load distribution and dynamic response of Ⅰ-shaped steel columns subjected to close-in explosions
摘要
Abstract
Steel columns are the important load-carrying members in steel structures.However,there is still a lack of studies on the blast load distribution and dynamic response of steel columns subjected to close-in explosions,especially for the effect of angles of incidence on the blast load and dynamic response of steel columns.In this study,LS-DYNA software is used to investigate the blast load distribution and dynamic response of I-shaped steel columns subjected to close-in explosions under different angles of incidence.The following conclusions can be drawn when the strong axis of the column is loaded with shock wave,the clearing wave effect has a significant influence on the blast load distributed over the flange on the attack side.Compared with the case of an infinite reflecting surface,the reflected impulse on the flange is reduced by 10％-50％.The velocity of the clearing wave in close-in explosions is much higher than the ambient sound velocity assumed in the current blast-resistant design guidelines,which indicates that the ambient sound velocity assumption is not applicable to close-in explosions.When the shock wave impacts on the weak axis,the clearing effect is insignificant.Due to the multiple reflections of the shock wave in the region between the flanges and the web,the positive phase duration is enlarged.This gives a rise to a higher maximum impulse on the web than that in the case of an infinite reflecting surface.For α＜α0(α0 is the critical angle of incidence which goes through the end of the flange on the attack side to the center of the I-shaped cross section),the main action zone of the shock wave is the flange-web-flange region.The blast load and local deformation of the web achieve the maximum at 30°.The two half-flanges open outwards,and the opening amplitude decreases with the angle of incidence.For α＞α0,the shock wave is mainly loaded on the flange.Its blast load and global deflection reach the maximum at 90°.The two half-flanges close inwards,and the closing amplitude increases with the angle of incidence.关键词
工字形截面钢柱/近距离爆炸/爆炸荷载/数值模拟/变形模式/入射角/稀疏波效应Key words
Ⅰ-shaped steel column/close-in explosion/blast load/numerical simulation/deformation mode/angle of incidence/clearing effect分类
建筑与水利引用本文复制引用
肖伟芳,陈思琦,赵宪忠..近距离爆炸作用下工字形截面钢柱荷载分布与动态响应数值模拟研究[J].建筑结构学报,2024,45(1):12-26,15.基金项目
国家自然科学基金项目(52278521),中央高校基本科研业务费专项(22120210415,22120220208,22120230230). （52278521）
