锚固力在钢筋黏结和端板承压间的分配规律  

Distribution regulation of the reinforcement force between bond and headed bars

作　　者：郑文忠[1] 苗天鸣 王识宇 王英[1] ZHENG Wenzhong;MIAO Tianming;WANG Shiyu;WANG Ying(Key Laboratoiy of Structures Dynamic Behavior and Control （Harbin Institute of Technology） , Ministiy of Education,Harbin 150090,China)

机构地区：[1]结构工程灾变与控制教育部重点实验室(哈尔滨工业大学),哈尔滨150090

出　　处：《哈尔滨工业大学学报》2018年第6期152-160,共9页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金(51378146);教育部博士点基金(20132302110064);黑龙江省自然科学基金重点项目(ZD2015010)

摘　　要：为获得锚固力在高强热轧钢筋直锚段黏结和端部锚固板承压间的分配规律,以钢筋与混凝土间的黏结-滑移本构关系为基础,利用MATLAB编写出带锚固板钢筋受力计算程序,并通过120个带锚固板钢筋混凝土试件的拉拔试验结果对程序的准确性进行验证.依托程序,分析相对保护层厚度c/d和钢筋屈服强度与混凝土抗拉强度之比fy/ft,对钢筋稳定锚固长度与钢筋公称直径之比las/d的影响以及钢筋屈服强度、混凝土强度等级、混凝土相对保护层厚度、钢筋相对埋置长度等参数对直锚段钢筋黏结应力fb的影响,并拟合得到以fy/ft和c/d为自变量的las/d计算公式.结果表明:las/d随fy/ft的增大而线性增大,随c/d的增大而非线性减小;fb/fy随钢筋埋置长度与稳定锚固长度之比lat/las的变化规律只与混凝土相对保护层厚度有关.继而通过拟合得到加载端钢筋受拉屈服强度时刻,以c/d和lat/las为自变量的fb/fy计算公式.Based on the bond stress-slip constitutive model between the reinforcement and concrete,a MATLAB program was coded to calculate the force of the headed bars,which was used to obtain the regulation of distribution between bond and headed bars of the high strength hot-roll reinforcement force,and it was validated by the pull-out tests of 120 reinforced concrete specimens. According to the simulation results,the combined effects of the relative concrete cover（ the ratio of concrete cover c to bar diameter d） and an index fy/ftindicating the ratio of reinforcement yield strength to concrete tensile strength were investigated quantitatively. The results indicate that las/d（ the ratio of the stable development length to bar diameter） increases linearly with fy/ftincrease,but gradually decreases with the increasing c/d. The formula of las/d for fy/ftand c/d was established,and the potential influence factors of the bond stress fbwere evaluated,including reinforcement yield strength,concrete tensile strength,the relative concrete cover and the embedment length lat. The results indicate that c/d is the only factor to constrain the parameter fb/fyto be varied with the index lat/las. A reliable calculation formula of the fb/fyfor c/d and lat/laswas proposed.

关 键 词：直锚段黏结力 稳定锚固长度 锚固板承压力 分配规律 

分 类 号：TU375.1[建筑科学—结构工程]