钢梁应力感应电动势效应及其谱线变化研究

发布时间：2018-03-15 05:05

本文选题：钢梁　切入点：翼缘　出处：《东北大学》2013年硕士论文　论文类型：学位论文

【摘要】：钢结构与其他结构相比,具有许多优点,是建筑工程中广泛应用的一种重要结构形式。但钢结构在具体应用中,也会产生一些质量问题,会发生一些工程事故,所以应采取一些积极措施加以预防。随着电子技术、传感技术、新材料、新工艺等多领域的发展,测试技术也有了很大的发展,内容也逐渐丰富,涉及到了物理学、电子学、材料学等多种学科的内容。综合利用测试技术基础知识和技能可以提高分析、解决工程实际问题的能力。这使得测试技术既有较深的理论性,又有较强的实践性。以往的多数研究,都是根据受弯构件的应力与应变来研究构件的性能,而且在实际工程中存在很多限制,难以应用于实际工程。而现有的对在役钢结构的无损检测技术并不十分完整,不仅效果有限而且存在着很多问题。本题目的理论意义就是,希望通过对电动势谱线与应力的联系,在不依赖形变的基础上得出受弯构件的性能。本文采用电磁检测方法为对钢梁翼缘加以磁场,本实验采用了精密度较高的自制传感器使钢梁产生感应电动势,并通过旋转传感器的加载方向在不同角度产生的感应电动势与外加应力相应的变化进行分析,得出应力、应变、角度和感应电动势的关系,并绘制曲线图形,通过分析,总结相应的规律。本实验针对H型钢梁在纯弯曲实验中,下翼缘中点处的挠度过大引起传感器难以紧密接触到磁场加载区,无法正常加载稳定磁场的问题,本实验采取了把测点移动到钢梁相同弯矩范围内偏移中心25cm的挠度较小处的方法。最后得出以下结论：1.变换测点位置之后,传感器不仅能够加载稳定的磁场,也能起到对传感器的保护作用。2.钢梁下翼缘受拉区当磁场为顺力方向时,感应电动势变化量小,垂直力方向下的变化量大。3.把传感器露在外边的两个加载端使用优质绝缘胶带进行绝缘能有效改善传感器的加载效果。4.将试验室取得的感应电动势之和与应力的关系曲线为应力已知标准曲线,为实测的感应电动势数据提供依据,进而确定被测应力值。5.实验数据表明外加应力对磁矩变化的影响与感应电动势随角度变化的理论一致。
[Abstract]:Compared with other structures, steel structure has many advantages and is an important structural form widely used in building engineering. However, some quality problems and engineering accidents will occur in concrete application of steel structure. So we should take some positive measures to prevent it. With the development of electronic technology, sensing technology, new materials, new technology and so on, the testing technology has also made great progress, and the content has been gradually enriched, involving physics, electronics, etc. The comprehensive use of basic knowledge and skills of test technology can improve the ability of analysis and solving practical engineering problems. Most previous studies have studied the performance of members according to the stress and strain of bending members, and there are many limitations in practical engineering. It is difficult to be applied to practical engineering. However, the existing nondestructive testing technology for existing steel structures is not very complete, not only has limited effect, but also has many problems. The theoretical significance of this topic is:. It is hoped that the properties of bending members can be obtained on the basis of the relationship between the electromotive force spectrum line and the stress and on the basis of independent deformation. In this paper, the electromagnetic detection method is used to apply magnetic field to the flange of the steel beam. In this experiment, a self-made sensor with high precision is used to make the steel beam produce induction electromotive force, and the stress and strain are obtained by analyzing the corresponding changes of the induction electromotive force and the applied stress produced by the loading direction of the rotating sensor at different angles. The relationship between angle and inductive electromotive force, drawing curve figure, summarizing the corresponding law through analysis. This experiment is aimed at the pure bending experiment of H-shaped steel beam. The deflection at the midpoint of the lower flange makes it difficult for the sensor to be in close contact with the magnetic field loading area and can not normally load a stable magnetic field. This experiment adopts the method of moving the measuring point to the smaller deflection of the center of 25 cm deviation within the same bending moment of the steel beam. Finally, the following conclusion is drawn: 1. After changing the position of the measuring point, the sensor can not only load a stable magnetic field, It can also protect the sensor. 2. When the magnetic field is in the direction of forward force, the change of induction electromotive force is small. The two loading ends exposed to the sensor can effectively improve the loading effect of the sensor by using high quality insulating tape for insulation. 4. The sum of the induced EMF and the stress obtained in the laboratory can be improved. The relation curve is the standard curve of known stress. The experimental data show that the effect of the applied stress on the magnetic moment is consistent with the theory that the induced EMF varies with the angle.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU391

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