碳纤维片材加固RC梁四点弯曲的多重开裂分析  

Analysis of Multiple Cracking of Carbon Fiber Sheet-Reinforced RC Beam Under Four-Point Bending

作　　者：曾庆敦[1] 陈汐龙[1] 谭茶生[2] 

机构地区：[1]华南理工大学交通学院,广东广州510640 [2]华南理工大学建筑学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2007年第2期13-17,22,共6页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(10372032);广东省自然科学基金资助项目(031394)

摘　　要：借鉴复合材料力学的分析方法,建立一种分层剪滞模型,研究了碳纤维片材加固钢筋混凝土梁在四点弯曲载荷作用下的多重开裂破坏,求得了梁纯弯段下部钢筋保护层中的最大裂缝宽度和裂缝密度与施加载荷和碳纤维片材的粘贴层数之间的定量关系,计算结果与现有实验值较吻合.结果表明:施加载荷愈大,裂缝密度和宽度愈大;随着碳纤维片材粘贴层数的增加,裂缝间距明显变小,最大裂缝宽度则基本保持稳定;在碳纤维片材粘贴层数较小的情形下,当施加载荷达到或超过某值时,梁纯弯段下部混凝土保护层将出现饱和裂缝群.With the aid of the analytical methods of composite mechanics, a layered shear-lag model is established to investigate the multiple cracking of reinforced concrete （RC） beam reinforced with carbon fiber sheets under four-point bending. The relationships between the crack items and the applied load as well as the number of carbon fiber sheets are then obtained, where the crack items include the crack density and the maximum crack width in the reinforcement cover under the pure bending part of the beam. The calculated results are in good agreement with the existing experimental ones, showing that （1） the crack density and width increase with the applied load; （2） with the increase of the number of carbon fiber sheets, the crack spacing obviously becomes small, while the maximum crack width almost remains constant; and （3） in the case of a small number of carbon fiber sheets, a duster of saturation cracks emerge in the reinforcement cover under the pure bending part of the beam when the applied load reaches or exceeds a certain value.

关 键 词：碳纤维片材加固混凝土梁 四点弯曲 剪滞分析 裂缝密度 最大裂缝宽度 

分 类 号：U414.1[交通运输工程—道路与铁道工程] O346.1[理学—固体力学]