摘要
采用考虑子结构边界约束条件的数值分析模型,将钢梁在爆炸作用下的变形损伤引入子结构抗倒塌分析,建立了评估钢框架梁柱子结构爆炸后抗倒塌性能降低程度的压力-冲量曲线图及表达式,并分析梁端约束刚度及钢梁跨高比的影响。结果表明,抗倒塌阶段的前期出现压拱机制,随后经由梁机制过渡至悬链线机制,且抗倒塌性能降低程度与爆炸强度为非单调关系;除铰接约束外,水平约束刚度对子结构竖向承载力的发展过程影响不明显;随着钢梁跨高比的减小,产生相同降低指数所需的超压和冲量均增大,但当跨高比降至一定程度时,子结构趋于剪切变形模式,导致悬链线阶段的极限变形和最大竖向承载力均有所下降。
The numerical analysis model that considers the boundary condition of substructure was used,the deformation and damage of steel beam under blast loading were introduced into the anticollapse analysis of substructures,and the pressure-impulse curve plot and expression were established to evaluate the anti-collapse performance of steel frame beam-column substructures subjected to explosion.The parametric analysis was conducted out to investigate the effect of restraint stiffness and span-depth ratio.The results show that the arch action occurs at the first stage,then the flexural action works and the catenary action plays a key role finally.The reduction degree of anti-collapse performance of substructures may exhibit non-monotonic behavior as the intensity of the explosion increases.Except for the hinge joint,horizontalrestraint stiffness has a less effect on the development of the vertical resistance.The overpressure and impulse corresponded to the same index increases with the decrease of the span-depth ratio,but the substructure will trend to the shear deformation mode when the span depth ratio decreases to a low level,leading to the decrease of the ultimate deformation and maximum vertical resistance at the stage of catenary action stage.
作者
陈晔
李毅
杜一鸣
史可贞
刘晅亚
CHEN Ye;LI Yi;DU Yi-ming;SHI Ke-zhen;LIU Xuan-ya(Tianjin Fire Science and Technology Research Institute of MEM,Tianjin 300381,China;Key Laboratory of Building Fire Protection Engineering and Technology,MEM,Tianjin 300381,China;School of Civil Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Fire Fighting and Rescue Technology of MPS,Hebei Langfang 065000,China)
出处
《消防科学与技术》
CAS
北大核心
2020年第8期1062-1065,共4页
Fire Science and Technology
基金
国家自然科学基金项目(51708125)
灭火救援技术公安部重点实验室开放课题项目(KF201708)。
关键词
爆炸
梁柱子结构
损伤
抗倒塌性能
参数分析
blast
beam-column substructure
damage
anti-collapse performance
parametric analysis
