基于冲击-光纤法的焊接型钢梁损伤检测理论与实验研究  

Damage detection at the web/flange junction of welded I-section steel beam based on the impact-optic technique

作　　者：许颖[1] 牛丽 祖红光 XU Ying;NIU Li;ZU Hongguang(Shenzhen Graduate School,Harbin Institute of Technology,Shenzhen518055,China)

机构地区：[1]哈尔滨工业大学深圳研究生院,广东深圳518055

出　　处：《振动与冲击》2018年第24期123-130,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金面上项目(51778191);深圳市科技计划项目(JCYJ20170307145853300)

摘　　要：焊接型Ⅰ形钢是工程上普遍使用的钢材,在循环荷载下在翼缘与腹板的连接处容易发生疲劳破坏。由于破坏的突发性和损失的惨重性,需要及时检测到损伤的发生。在探究钢梁内应力波传播机理的基础上,利用小锤敲击钢梁表面产生宽频冲击波,通过粘贴在Ⅰ形钢梁表面的光纤干涉仪接收应力波信号,通过对信号频谱分析,判断损伤的存在以及位置。数值分析和实验研究结果表明,采用冲击-光纤法检测焊接型Ⅰ形钢梁翼缘与腹板连接处疲劳损伤具有可行性。Welded I-section steel members are widely used in engineering,and it is prone to fatigue damage at the web/flange junction under cyclic load.Due to the sudden damage and the heavy losses,it is necessary to detect the damage in time.Based on the study of stress wave propagation mechanism in steel beam,a broadband impact wave was generated by a hammer striking on the surface of a steelⅠ-beam,and the fiber interferometer was attached to the surface of steel beam to receive the stress wave signal.By analyzing the impact echo signal spectrum,the existence and location of the damage was determined.Numerical analysis and experimental results show that it is feasible to detect the fatigue damage at the flange/web junction of the steelⅠ-beam by the impact-optic method.

关 键 词：冲击回波 光纤干涉仪 频谱 疲劳损伤 快速傅里叶(FFT) 

分 类 号：TU311.3[建筑科学—结构工程]