학술논문
基于超声多尺度衰减的螺栓轴向应力评价 / Evaluation of the axial stress in bolts based on the ultrasonic multi-scale attenuation method
Document Type
Academic Journal
Author
Source
振动与冲击 / Journal of Vibration and Shock. 43(2):226-233
Subject
Language
Chinese
ISSN
1000-3835
Abstract
针对超声波传统衰减法测量高强度短螺栓应-力时,难以达到预期精度,提出了一种基于超声散射衰减理论和小波多尺度分解的测量螺栓应力的方法.基于立方晶系材料的瑞利散射,推导了超声衰减系数与应力关系的理论模型.利用小波变换得到各个尺度的衰减系数并定义加权超声多尺度衰减系数,结合粒子群优化算法和灰色关联分析确定衰减系数最优尺度组合及其归一化权重系数,建立轴向应力的超声多尺度衰减测量模型.利用搭建的螺栓轴向应力超声波测量系统,对普通螺栓进行轴向应力测量,证明了该方法的可行性.对比了多尺度衰减法与渡越时间和传统衰减法对高强度短螺栓轴向应力的测量结果,验证了多尺度超声衰减法更适合高强度短螺栓的轴向应力测量.
Aiming at the difficulty in achieving expected accuracy when measuring the stress of high-strength short bolts by the ultrasonic conventional attenuation method,a method based on the ultrasonic scattering attenuation theory and wavelet multiscale decomposition was proposed to measure the stress of bolts.Firstly,a theoretical model for the relationship between the ultrasonic attenuation coefficient and axial stress was derived based on the Rayleigh scattering of cubic crystal system materials.The wavelet transform was used to obtain the attenuation coefficients of each scale and define the weighted ultrasonic multiscale attenuation coefficients.The particle swarm optimization algorithm and gray correlation analysis were combinedly used to determine the optimal scale combination of the attenuation coefficients and their normalized weight coefficients,and an ultrasonic multiscale attenuation model was established for the measurement of the axial stress.Then,using the constructed bolt axial stress ultrasonic measurement system,the axial stress of common bolts was measured,and the feasibility of the method was demonstrated.Finally,the results of the axial stress measurement of high-strength short bolts by the multi-scale attenuation method were compared with those by the transition time method and the traditional attenuation method.It is verified that the ultrasonic multiscale attenuation method is more suitable for the axial stress measurement of high-strength short bolts.
Aiming at the difficulty in achieving expected accuracy when measuring the stress of high-strength short bolts by the ultrasonic conventional attenuation method,a method based on the ultrasonic scattering attenuation theory and wavelet multiscale decomposition was proposed to measure the stress of bolts.Firstly,a theoretical model for the relationship between the ultrasonic attenuation coefficient and axial stress was derived based on the Rayleigh scattering of cubic crystal system materials.The wavelet transform was used to obtain the attenuation coefficients of each scale and define the weighted ultrasonic multiscale attenuation coefficients.The particle swarm optimization algorithm and gray correlation analysis were combinedly used to determine the optimal scale combination of the attenuation coefficients and their normalized weight coefficients,and an ultrasonic multiscale attenuation model was established for the measurement of the axial stress.Then,using the constructed bolt axial stress ultrasonic measurement system,the axial stress of common bolts was measured,and the feasibility of the method was demonstrated.Finally,the results of the axial stress measurement of high-strength short bolts by the multi-scale attenuation method were compared with those by the transition time method and the traditional attenuation method.It is verified that the ultrasonic multiscale attenuation method is more suitable for the axial stress measurement of high-strength short bolts.