配筋率与质量比对FRP-RC梁冲击响应与损伤的影响  

Effect of FRP reinforcement ratio and mass ratio on impact response and damage of FRP-RC beams

作　　者：金浏[1] 郑敏[1] 张仁波[1] 杜修力[1] Jin Liu;Zheng Min;Zhang Renbo;Du Xiuli(Key Laboratory of Urban Security and Disaster Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学城市减灾与防灾防护教育部重点实验室,北京100124

出　　处：《东南大学学报（自然科学版）》2024年第4期816-826,共11页Journal of Southeast University：Natural Science Edition

基　　金：北京市自然科学基金资助项目(JQ22025);国家自然科学基金资助项目(52308130)。

摘　　要：基于考虑应变率效应的三维数值模型,对玄武岩纤维增强复材筋混凝土(BFRP-RC)梁的抗冲击性能进行了研究.分析了冲击体与FRP-RC梁质量比、配筋率等因素对冲击响应的影响规律.结果表明,随着质量比增大,FRP筋混凝土梁的破坏模式从弯曲破坏转变为剪切破坏,但是配筋率的改变并不影响梁的破坏模式.由于BFRP筋弹性模量低,并且没有屈服阶段,故即使在梁损伤比较严重的情况下,BFRP筋的应变和BFRP筋梁的位移也会发生较大恢复.在冲击过程中,冲击力时程曲线的形状与质量比之间的规律不随配筋率而改变.此外,以剩余承载力为基准,建立了以频率变化、损伤因子和峰值位移为指标的损伤评估方法,为实际工程中FRP筋混凝土梁构件的灾后处置提供理论基础.The impact resistance of basalt-fiber-reinforced-polymer bars reinforced concrete(BFRP-RC)beams is studied based on a three-dimensional numerical model considering strain rate effect.The influence of the mass ratio of the impact hammer to the FRP-RC beam and the reinforcement rate on the beams'impact response is analyzed.The results indicate that the damage mode of FRP-RC beams changes from bending damage to shear damage as the mass ratio increases.However,the change in the reinforcement rate does not affect the damage mode of the beams.Due to the low elastic modulus of BFRP bars and the absence of a yielding stage,large recovery of strain in BFRP reinforcement and displacement in BFRP-RC beams occurs even in the case of a severe damaged beam.During the impact process,the relationship between the shape of the impact force-time curve and the mass ratio remains constant regardless of the reinforcement ratio.Furthermore,a damage assessment method with frequency variation,damage factor and peak displacement as indicators is established based on the residual bearing capacity,which provides a theoretical basis for the post-disaster disposal of FRP-RC beam in actual engineering.

关 键 词：落锤冲击 损伤评估 数值模拟 FRP-RC梁 质量比 

分 类 号：U441[建筑科学—桥梁与隧道工程]