摘要
钢筋混凝土(RC)深梁的传力机制与一般梁不同。考虑钢筋和混凝土的材料性能以及二者之间黏结强度的应变率效应,借助三维非线性有限元模型对冲击荷载作用下RC深梁的动力响应开展了数值模拟研究,并探讨了跨高比、冲击质量和受拉钢筋配筋率对RC梁破坏模式、跨中挠度、冲击力和支反力的影响。结果表明:冲击荷载作用下,RC深梁主要发生冲剪破坏;随着跨高比增大,破坏模式由剪切为主转变为弯曲为主,跨中挠度与净跨的比值减小;RC梁的跨中挠度、冲击力持续时间和支反力作用时间随冲击质量增大而线性增加;在一定范围内提高受拉钢筋配筋率可减轻RC梁的损伤并减小跨中位移。
Force transfer mechanism of reinforced concrete(RC)deep beams is different from that of normal beams.The dynamic response of RC deep beams subjected to impact loadings were investigated with the three-dimensional nonlinear finite element model,considering the strain rate on material property of steel rebar and concrete as well as the bond strength between them.The influence of span-to-height ratio,impact mass and tensile reinforcement ratio on the failure mode,mid-span deflection,impact force and reaction force of RC beams was discussed.It was found that RC deep beams mainly experience punching-shear failure under impact loadings.With the increase in span-to-height ratio,the failure pattern of RC beams changes from shear-dominant to flexural-dominant.The ratio between mid-span deflection and clear span decreases with respect to span-to-height ratio.With the increase in impact mass,the mid-span deflection,durations of impact force and reaction force increase linearly.Increasing the tensile reinforcement ratio within a certain range can reduce the damage of the RC beam and reduce the mid-span displacement.
作者
石磊
张仁波
兰钰昌
金浏
杜修力
SHI Lei;ZHANG Renbo;LAN Yuchang;JIN Liu;DU Xiuli(China Building Technique Group Co.,Ltd.,Beijing 100013,China;Key Laboratory of Urban Security and Disaster Engineering,Ministry of Education,Beijing University of Technology,Beijing 100124,China)
出处
《混凝土》
CAS
北大核心
2023年第10期32-36,41,共6页
Concrete
基金
国家重点研发计划专项(2019YFC1511003)
国家自然科学基金(51822801)。
关键词
钢筋混凝土深梁
冲击荷载
动力响应
配筋率
冲击质量
RC deep beam
impact loading
dynamic response
tensile reinforcement ratio
impact mass
