摘要
研究目的:针对HRB400、HRBF400、HRB500、HRBF500共4种规格的高强钢筋电弧搭接焊连接,开展包含不同直径和应力比的疲劳试验,获得高强钢筋的p-S-N曲线,为高强钢筋在铁路工程的合理高效利用提供坚实数据支撑。研究结论:(1)试验共计完成有效试件124个,获得了9条高强钢筋电弧搭接焊连接接头的S-N曲线;(2)试验数据表明加载频率对疲劳试验结果无明显影响,随着应力比、钢筋直径的增加,疲劳强度略有下降;(3)将所有试验数据通过总体回归,得到存活率R=95%、置信度C=75%的p-S-N曲线作为铁路工程用高强钢筋电弧搭接焊的设计S-N曲线,该曲线总体偏保守、适用范围广泛、便于运用;(4)总体回归的S-N曲线中高强钢筋电弧搭接焊接头的200万次中值疲劳强度约为82 MPa,在中等寿命区S-N曲线斜率为3.13;(5)本研究结果可为高强钢筋电弧搭接焊接头在铁路工程的应用提供依据,其他疲劳敏感工程也可参照使用。
Research purposes: For the lapped welded splices of HRB400, HRBF400, HRB500, HRBF500 high-strength reinforcing bar, the fatigue tests with different diameters and stress ratios are carried out, to obtain the p-S-N curve of the lapped welded splices, which can provide solid data support for the rational and efficient use of high-strength steel reinforcing bar in railway projects.Research conclusions:(1) 124 effective specimens were completed in the test, and S-N curves of 9 lapped welded splices were obtained.(2) The test data shows that the loading frequency has no significant effect on the fatigue test results. As the stress ratio and the diameter of the steel bar increase, the fatigue strength decreases slightly.(3) All test data are used by overall regression. The p-S-N curve with the survival rate R=95% and the confidence C=75% is used as the design S-N curve for lapped welded splices of railway engineering. The curve is generally conservative, has a wide range of applications, and is easy to use.(4) The mean fatigue strength of 2 million times cycles in the curve is about 82 MPa, and the S-N curve slope is 3.13 in the middle life zone.(5) In addition to railway engineering, the research results can provide a basis for the application of high-strength reinforcing bar lapped welded splices in railway engineering, and can also be used in other fatigue-sensitive engineering.
作者
王亚飞
王伟
刘迎倩
WANG Yafei;WANG Wei;LIU Yingqian(State Key Laboratory of Bridge Structure Health and Safety,Wuhan,Hubei 430034,China;China Railway Bridge Science Research Institute Ltd,Wuhan,Hubei 430034,China)
出处
《铁道工程学报》
EI
北大核心
2021年第3期113-117,共5页
Journal of Railway Engineering Society
基金
中国铁路总公司科研试验项目——铁路工程应用高强钢筋试验(Z2014-038)。
关键词
高强钢筋
疲劳试验
电弧搭接焊
S-N曲线
high strength reinforcement
fatigue test
lapped welded splices
S-N curve
