锈蚀程度对钢筋力学性能的影响规律研究

Influence Law Study of Corroded Steel Bars on Mechanical Properties

为研究锈蚀钢筋力学性质的衰变规律,基于概率统计学理论,采用人工加速锈蚀法对五种直径的HRB400钢筋实施锈蚀处理,并利用除锈剂除锈后进行室内拉伸试验。结果表明,随着钢筋锈蚀程度的增大,钢筋的名义屈服强度、名义极限强度均呈线性退化规律,钢筋断后伸长率呈先急后缓退化,非线性变化规律明显;在相同锈蚀条件下,大直径钢筋的名义屈服强度、名义极限强度和断后伸长率的退化速度较快,但与小直径钢筋无显著统计学差异。研究成果可为已建混凝土结构的承载力、耐久性等服役效能评价提供理论依据,对结构的加固补强、工程续建等施工方案的制定有重要的参考价值。

In order to study the decay law of mechanical properties of corroded steel bars, we applied the principle of probability and statistics. We carried out the corrosion treatment for 5 kinds of HRB400 steel bars by means of artificial acceleration corrosion method. And then the indoor tensile test was implemented after steel bars rust removal with rust remover. The results show that with the increase of corrosion degree, the nominal yield strength and nominal ultimate strength of steel bars are linearly degenerate, and the degradation of the percentage elongation after fracture of steel bars appeared the slow decline after a period of extreme decline; nonlinear variation is obvious. In the same corrosion condi tion, the nominal yield strength, the nominal ultimate strength and percentage elongation after fracture of the large diameter steel bar degrade faster, but it has no significant statistical difference with the small diameter steel bar. The conclu sion can provide a theoretical basis for the bearing force, durability and effectiveness evaluation in service of built concrete structures, and can also provide important reference value for the construction scheme of the reinforcement of structure and continued construction.