上海交通大学学报(自然版) ›› 2018, Vol. 52 ›› Issue (2): 152-162.doi: 10.16183/j.cnki.jsjtu.2018.02.005

• 学报(中文) • 上一篇    下一篇

腐蚀和疲劳耦合作用下Q345角钢拟静力试验研究

张春涛1,李正良2,王汝恒1   

  1. 1. 西南科技大学 土木工程与建筑学院, 四川 绵阳 621010; 2. 重庆大学 土木工程学院, 重庆 400045
  • 出版日期:2018-03-01 发布日期:2018-03-01
  • 基金资助:
    国家科技支撑计划项目 (2015BAL03B03),国家自然科学基金项目(51508482)

Quasi-Static Test of Q345 Equal Angles Under the Coupling Action of Corrosion and Fatigue Vibration

ZHANG Chuntao1,LI Zhengliang2,WANG Ruheng1   

  1. 1. School of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, Sichuan, China; 2. School of Civil Engineering, Chongqing University, Chongqing 400045, China
  • Online:2018-03-01 Published:2018-03-01

摘要: 基于环境腐蚀和疲劳振动的相互作用,建立了腐蚀疲劳耦合损伤模型,分析Q345角钢力学性能在腐蚀疲劳耦合作用下的退化规律.利用目标地区年降雨时间统计数据建立环境腐蚀模型,并将能量耗散与疲劳裂纹扩展Paris公式相结合给出衡量疲劳损伤的演化模型.与此同时,为有效衡量腐蚀与疲劳之间的相互关系提出耦合因子,并基于该因子将腐蚀和疲劳的损伤模型相结合建立腐蚀疲劳耦合损伤模型.最后,对20根规格为70mm×5mm的Q345等边角钢展开拟静力试验,分析腐蚀、疲劳及其偶合作用对角钢承载能力和耗能性能的影响规律,建立各参数耦合损伤退化模型.结果发现:腐蚀疲劳耦合作用能显著促进构件损伤的发展,但现行设计规范和研究很少考虑这种影响;Q345角钢的承载能力、滞回曲线形状和循环次数等均随腐蚀疲劳耦合作用增加发生了明显变化,加速腐蚀12h和疲劳振动4.0×104次的耦合作用使延性系数和累积耗能参数的退化率比两者单独作用造成的损伤总和多11.1%和7.7%.

关键词: 腐蚀疲劳, Q345等边角钢, 滞回性能, 耦合因子, 耦合损伤

Abstract: The coupling damage model of corrosion and fatigue is established considering the interaction between environmental corrosion and fatigue vibration. This model is applied to study the deterioration law of the mechanical property of Q345 equal angles. Firstly, the environmental corrosion model was established according to the annual rainfall time of the target areas, and the evolutionary model for evaluating fatigue damage was presented by combining energy dissipation model with Paris formula of fatigue crack growth. Then, a coupling factor was proposed to effectively measure the relationship between corrosion and fatigue damage. Based on this coupling factor, the coupling damage model was derived by combining the corrosion and fatigue damage models. Finally, the quasi-static test of twenty Q345 equal angles with 70mm×5mm specification was carried out, and the effect laws of the bearing capacity and energy dissipation performance of angle steels under the corrosion, fatigue and corrosion fatigue coupling actions were analyzed, and the coupling damage degradation model of each parameter was established. The results show that the coupling action of corrosion and fatigue promote the development of component damage, but current design specifications and studies rarely consider this effect. The bearing capacity, stiffness, hysteretic curve shape and cycle times of Q345 angle steels changed obviously due to the coupling action of corrosion and fatigue. Moreover, under the coupling action of 12 hours accelerated corrosion and 4.0×104 times fatigue vibration, the degradation rates of ductility coefficient and cumulative energy dissipation parameter were 11.1% and 7.7% more than the total the damage caused by the individual action of corrosion and fatigue damage.

Key words: corrosion fatigue, Q345 equal angles, hysteretic behavior, coupling factor, coupling damage model

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