基于分形理论的锈蚀钢筋力学性能研究  

Experimental Study on Mechanical Properties of Corroded Steel Bar Based on Fractal Theory

作　　者：江楠[1,2] 张海萍[1,2] 刘扬[1,2] 姜鸿涛 

机构地区：[1]长沙理工大学桥梁工程湖南省高校重点实验室,湖南长沙410114 [2]长沙理工大学土木与建筑学院,湖南长沙410114

出　　处：《实验力学》2017年第6期848-858,共11页Journal of Experimental Mechanics

基　　金：国家重点基础研究计划(973计划)(2015cb057704);国家自然科学基金资助项目(51378081)

摘　　要：为研究钢筋锈蚀后力学性能的退化规律,采用加速锈蚀方法获取锈蚀钢筋,对4根未锈蚀钢筋试件及20根锈蚀钢筋试件进行了拉伸试验。试验结果表明,在加速锈蚀条件下,锈蚀钢筋表面轮廓具有自相似性,可以用分形理论加以描述。锈蚀钢筋表面特征的不同对钢筋力学性能退化有一定影响,例如,应力-应变曲线发生明显变化,屈服强度、极限强度降低,屈服平台缩短直至消失。经过统计分析后,得出了锈蚀钢筋弹性模量、屈服强度、极限强度、极限应变等力学性能的回归公式,并在试验结果分析基础上,建立了与锈蚀表面特征参数相关的钢筋本构关系模型。上述结果可为锈蚀钢筋混凝土结构的计算及评估提供应用参考。In order to investigate the mechanical property deterioration of corroded steel bar,accelerated corrosion method was used to obtain corroded steel bars.Tensile experiment was carried out respectively for 4 specimens without corroded steel bars and 20 specimens with corroded steel bars.Experimental results indicate that under the accelerated corrosion condition,the surface profile of corroded steel bars has self-similarity,which can be described by fractal theory.Different surface characteristics of corroded steel bar have some influence on mechanical property degradation of steel bars.For example,stress-strain curve changes obviously,the yield strength and ultimate strength decrease,the yield platform is shortened until disappears.After statistical analysis,the regression formula of elastic modulus,yield strength,ultimate strength,ultimate strain and other mechanical properties of corroded steel bar were obtained.Based on analysis of experimental results,a constitutive model of steel bar related to characteristic parameters of corroded surface was established.Above results can be applied to the calculation and evaluation of corroded steel bar reinforced concrete structures.

关 键 词：钢筋 锈蚀 力学性能 分形特征 

分 类 号：TH16[机械工程—机械制造及自动化]