摘要
通过对12根CFRP筋珊瑚混凝土梁进行抗弯试验,研究配筋率、珊瑚混凝土强度对CFRP筋珊瑚混凝土梁开裂性能的影响,对裂缝的分布与裂缝宽度的发展规律、卸载后裂缝闭合情况、正常使用极限状态最大裂缝宽度限值对应荷载水平进行了分析。研究结果表明,提高CFRP筋配筋率和提高珊瑚混凝土强度均能有效控制CFRP筋珊瑚混凝土梁的最大裂缝宽度;梁试件卸载后裂缝出现闭合,配筋率越高,裂缝闭合越显著;CFRP筋珊瑚混凝土梁在达到正常使用极限状态时相对其极限承载力状态处于较低的荷载水平,因此其设计主要由正常使用极限状态控制。通过对试验数据的分析,对现有规范GB 50608中的短期最大裂缝宽度计算公式进行了修正,采用修正公式得到的最大裂缝宽度计算值与试验值吻合良好。
The influence of different reinforcement ratio and strength grade of coral concrete on cracking performance of coral concrete beams was studied by bending test of 12 carbon fiber reinforced polymer(CFRP)bars coral concrete beams,the development regularity of the distribution of cracks and crack width,the crack closure after unloading and the load level corresponding to the maximum crack width limit in the normal limit state are analyzed.The results show that the maximum crack width of CFRP reinforced coral concrete beams can be effectively controlled by increasing the reinforcement ratio of CFRP bars or the strength grade of coral concrete.The cracks of the beam specimens are closed after unloading,and the higher the reinforcement ratio,the more the crack closure is obvious.In addition,the specimens of CFRP bars reinforced coral concrete beams are at a lower load level when they reach the normal limit state of use,relative to their ultimate bearing capacity,the design of CFRP reinforced coral concrete beams is mainly controlled by the limit state of normal use.Through the analysis of the test data,the calculation formula of the maximum short-term crack width of the existing FRP design code GB 50608 is modified,and the calculated value of the maximum crack width obtained by the modified formula is in good agreement with the test value.
作者
邓志恒
黄潇霈
文坤
何宗院
刘兵
DENG Zhiheng;HUANG Xiaopei;WEN Kun;HE Zongyuan;LIU Bing(College of Civil and Architecture Engineering,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Engineering Safety of Guangxi,Guangxi University,Nanning 530004,China;China Railway siyuan Nanning Survey and Design Group Co.,Ltd.,Nanning 530004,China;Guangxi Hualan Design(Group)Co.,Ltd,Nanning 530004,China)
出处
《混凝土》
CAS
北大核心
2021年第4期34-39,共6页
Concrete
基金
国家自然科学地区基金项目(51868005)
广西自然基金项目(2018GXNSFAA050133)。
