摘要
针对管桩预应力钢筋断裂检测的难题,选取PHC450(95)管桩建立三维电磁场有限元模型,基于远场涡流检测原理分析激励线圈在管内外不同钢筋断裂工况下磁场信号的变化规律,探究合理的激励线圈、检测线圈布置方式和有效的磁场检测指标。结果表明:激励线圈在管内管外,磁感应强度径向分量、轴向分量的相位均可作为钢筋断裂的检测指标;激励线圈在管内,磁感应强度径向分量、轴向分量的幅值可检测是否有纵筋断裂;激励线圈、检测线圈靠近钢筋断裂环向位置才能检测到相对明显的磁场信号变化。可见,应用远场涡流法检测管桩钢筋断裂情况是可行的,为实际检测装备的研发工作奠定基础。
Aiming at the problem of fracture detection of prestressed steel bars in pipe piles,PHC 450(95)pipe pile was selected to establish a 3D finite element model of electromagnetic field.Based on the principle of remote field eddy current detection,the variation law of magnetic field signals of excitation coil both inside and outside the pipe were analyzed under different working condition of reinforced fracture,to explore the reasonable excitation coil,and detecting coil arrangement way and the effective magnetic field detection index.The results show that the phase of radial component of magnetic flux density can be used as the detection index of steel bar fracture when the incentive coil is both inside and outside the pipe.When the excitation coil is in the pipe,the amplitude of radial and axial component of magnetic flux density can be used to detect whether the longitudinal bars are broken.Only when the excitation coil and the detection coil are close to the fracture ring position of the steel bar can the relatively obvious magnetic field signal change be detected.It can be seen that it is feasible to use remote field eddy current method to detect steel bar fracture of pipe pile,which lays a foundation for the research and development of actual testing equipment.
作者
杨天凯
商峰
刘毅
YANG Tian-kai;SHANG Feng;LIU Yi(China Institute of Water Resources and Hydropower Research,Beijing 100038,China)
出处
《科学技术与工程》
北大核心
2020年第16期6613-6619,共7页
Science Technology and Engineering
基金
中国水利水电科学研究院基本科研业务费专项(SS0145B612017)。
关键词
预应力高强度混凝土管桩
钢筋断裂
远场涡流
数值分析
pre-stressed high-strength concrete pipe pile
steel bar fracture
remote field eddy current
numerical analysis
