基于超声波法的钢结构构件应力检测方法研究

发布时间：2018-03-16 03:08

本文选题：超声波法　切入点：临界折射纵波　出处：《哈尔滨工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：在役钢结构构件内部初始应力是钢结构安全性评价的重要指标。传统的应力检测方法，如电阻应变计法、X射线法、磁弹性法等，，不能同时满足在役钢结构构件内部应力、初始应力和无损检测的要求。针对上述问题，鉴于超声波法在焊接、铁路等领域应力检测的应用，本文提出了采用超声波对钢结构构件内部初始应力进行检测的方法，内容主要包括下列三个方面：基于超声波法的钢结构构件应力检测公式推导。本文在声弹性理论的基础上，选择了临界折射纵波作为应力检测的波型，推导了适合在役钢结构构件内部初始应力检测的公式。鉴于钢结构构件暴露于室外，温度对测量结果的影响不可忽视，分别给出了在考虑温度变化和不考虑温度变化两种情况下的应力-声时表达式。基于超声波法的钢结构构件应力检测系统搭建。根据理论推导和临界折射纵波法的特点，本文搭建了基于超声波法的钢结构构件应力检测系统。明确了各个仪器需要满足的参数和组合方法，完成了硬件系统的搭建；编译了对信号和数据处理的软件系统，建立了信号去噪、脉冲来临时刻捕捉、应力-声时差系数标定及钢结构构件应力求解等模块；给出了应力检测在本文搭建测试系统上的实现过程。基于超声波法的钢结构构件应力检测试验和验证。通过本文搭建的钢构件应力检测系统进行了应力检测试验，并用电阻应变片法对测量结果进行了验证。结果表明，超声波法应力检测结果真实可靠。通过对试验过程中可能造成误差的过程进行分析，给出了试验过程中需要注意的事项。最后，鉴于应力-声时差系数的重要性，重点研究了探头位置、声程等因素对应力-声时差系数的影响。从试验和分析结果可以看出，本文实现了用超声波法对使用状态下钢结构构件内部工作应力进行检测这一目标，且检测结果准确、操作方便。
[Abstract]:The internal initial stress of in-service steel structure member is an important index of safety evaluation of steel structure. Traditional stress detection methods, such as resistance strain gauge method, magnetoelastic method, etc., can not satisfy the internal stress of in-service steel structure members at the same time. The requirements of initial stress and nondestructive testing. In view of the application of ultrasonic method in welding, railway and other fields, this paper puts forward a method to detect the initial stress of steel structure by ultrasonic wave. The content mainly includes the following three aspects:. On the basis of the theory of acoustoelasticity, the critical refraction longitudinal wave is chosen as the wave type of stress detection. A formula for internal initial stress detection of steel structural members in service is derived. In view of the exposure of steel structural members to the outside, the influence of temperature on the measurement results cannot be ignored. The expression of stress-acoustic time is given under the condition of considering temperature change and not considering temperature change. The stress detection system of steel structure based on ultrasonic method is built. According to the characteristics of theoretical derivation and critical refraction longitudinal wave method, In this paper, the stress detection system of steel structure based on ultrasonic method is built. The parameters and combination methods of each instrument are defined, the hardware system is built, and the software system of signal and data processing is compiled. The modules of signal denoising, pulse timing capture, stress-acoustic time difference coefficient calibration and stress solution of steel structure members are established, and the realization process of stress detection in this paper is given. The stress detection test of steel structure based on ultrasonic method is carried out. The stress detection test is carried out through the steel member stress detection system built in this paper, and the results are verified by the resistance strain gauge method. The results show that, The results of ultrasonic stress detection are true and reliable. Through the analysis of the process that may cause errors in the test process, the matters needing attention in the test process are given. Finally, in view of the importance of the stress-acoustic time difference coefficient, The influence of probe position, sound path and other factors on the stress-acoustic time difference coefficient is studied emphatically. From the test and analysis results, it can be seen that the purpose of detecting the internal working stress of steel structure members under the condition of using the ultrasonic method is realized in this paper. And the detection result is accurate, the operation is convenient.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU391;TU317

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