摘要
【目的】钢结构长期服役过程中,钢构件的应力状态是评估结构安全与健康状态的关键参数。现有基于磁感电动势效应的应力检测方法未考虑磁场方向的影响,磁场角度变化会降低检测结果准确性。因此,通过理论分析和试验研究,量化磁场角度对钢结构柱磁感电动势-应力关系的影响程度。【方法】设计Q235B H型钢短柱轴心受压试验,将锰锌铁氧体U型电磁传感器固定于钢翼缘中心并改变其角度。分级加载过程中,同步采集不同应力水平、不同磁场角度下的磁感电动势信号,所有试验重复两次以保证数据可重复性。基于试验数据,建立不同磁场角度下H型钢柱的磁感电动势-应力关系曲线,分析磁场角度对H型钢柱应力与磁感电动势关系的具体影响规律,明确磁感电动势与应力、磁场角度的定量关系,同时通过磁感电动势梯度均值量化磁场角度对钢结构柱磁感电动势-应力关系的影响程度。【结果】在弹性范围内,磁感电动势与压应力呈显著线性负相关。随着磁场角度的增大,磁感电动势-应力关系曲线的斜率变化显著;磁场方向与主压应力方向平行时,信号灵敏度最高;随着磁场角度的增大,灵敏度呈非线性递减,垂直时灵敏度最低,且不同角度下的关系曲线互不相交。【结论】不同磁场角度下,磁感电动势梯度随应力增加趋于定值,且其均值随磁场方向与加载方向偏离角度的增大而减小,表明磁场角度会影响应力检测结果。基于试验结果建立的磁感电动势-应力数学表达式拟合度较好,且磁感电动势梯度均值与磁场角度符合余弦函数关系。
[Objective]The stress state of steel components is a key parameter for assessing the safety and health of steel structures during long-term service.Existing stress detection methods based on the magnetically induced electromotive force effect do not consider the influence of the magnetic field direction,and variations in the magnetic field angles reduce the accuracy of detection results.Therefore,this study quantitatively investigates the influence of the magnetic field angle on the relationship between stress and magnetically induced electromotive force in steel structural columns through theoretical analysis and experimental research.[Methods]Axial compression tests on short Q235B H-shaped steel column specimens were designed.A manganese-zinc ferrite U-shaped electromagnetic sensor was fixed at the center of the steel flange,and its orientation was varied.During the graded loading process,magnetically induced electromotive force signals at different stress levels and magnetic field angles were collected simultaneously.All tests were repeated twice to ensure data reproducibility.Based on the experimental data,magnetically induced electromotive force-stress relationship curves at different magnetic field angles were established.The specific influence of magnetic field angle on this relationship was examined,and the quantitative relationship among magnetically induced electromotive force,stress,and magnetic field angle was clarified.In addition,the mean gradient of the magnetically induced electromotive force was used to quantify the effect of magnetic field angle on the electromotive force-stress relationship.[Results]Within the elastic range,the magnetically induced electromotive force shows a significant linear negative correlation with compressive stress.The slope of the relationship curve changes markedly with increasing magnetic field angle.The signal sensitivity is the highest when the magnetic field direction is parallel to the principal compressive stress direction.As the magnetic field angle increases,the sensitivity decreases nonlinearly and reaches its minimum value when the magnetic field direction is perpendicular to the stress direction.The characteristic curves corresponding to different angles do not intersect.Under different magnetic field angles,the gradient of the magnetically induced electromotive force tends toward a constant value with increasing stress,and its mean value decreases as the deviation angle between the magnetic field direction and the loading direction increases.[Conclusions]The magnetic field angle affects the accuracy of stress detection.The mathematical expression for the relationship between magnetically induced electromotive force and stress established based on the experimental results shows a good fit.Furthermore,the mean gradient of the magnetically induced electromotive force follows a cosine-function relationship with the magnetic field angle.
作者
何连昇
陈猛
HE Liansheng;CHEN Meng(School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,Liaoning,China)
出处
《沈阳工业大学学报》
北大核心
2026年第1期120-127,共8页
Journal of Shenyang University of Technology
基金
辽宁省自然科学基金项目(2024-MSBA-28)。
关键词
钢结构柱
磁感电动势
磁场角度
应力
角度效应
磁信号梯度
定量模型
无损检测
steel structural column
magnetically induced electromotive force
magnetic field angle
stress
angular effect
magnetic signal gradient
quantitative model
nondestructive testing
