基于两参数的FRP-混凝土界面黏结滑移本构关系研究

摘要

为了解决纤维增强复合材料(FRP)-混凝土(以下简称 RC)界面应力-滑移本构关系中参数多,且不利于工程测量的问题,设计一组具有不同混凝土强度(C30、C40、C50)且每一强度有6种不同界面粗糙程度的混凝土试件共计54个,通过单剪试验,并结合118组已有试验数据对界面参数进行精简,选择了更适合工程应用的两参数来表达RC界面本构关系.结果表明:采用改进后的两参数(混凝土抗压强度fc、混凝土表面粗糙度fi)来反映C30、C40、C50 的 RC界面黏结应力-滑移本构关系要优于现有大多数模型,fc对本构关系的贡献要大于fi.所提本构关系理论计算值小于实测值,最大误差为9%,具有一定安全储备,有利于工程实际应用.%In order to solve the problem that there are too many parameters in interfacial stress-slip constitutive relation between fiber reinforced polymer (FRP)and concrete (be short for RC)which are hard to measure for engineering,a total of fifty-four concrete pieces with a set of different strengths of concrete(C30,C40,C50)and six different interfacial roughness in each set are designed. Combining with 1 1 8 groups of existing experimental data to simplify the interfacial parameters,and adopting single shear test,the two parameter constitutive relation is established which is more suitable for engineering practical.Results show that the improved two parameters (concrete compressive strength f c,concrete surface roughness fi)can better reflect the RC interfacial bond stress-slip constitutive relation of C30,C40,C50 concrete than the most existing models,and the parameter f cis more significant in this constitutive relation than fi.The theoretical calculation value of the proposed constitutive relation is less than the measured value,the maximum error is 9 %.The certain security reserve shows that it is helpful to engineering application.