自由锚杆纵向超声导波特性理论计算与试验研究  

Theoretical calculation and experimental study on the characteristics of longitudinal ultrasonic guided wave propagation in a free bolt

作　　者：张小明[1] 李卓然 李智 禹建功[1] ZHANG Xiaoming;LI Zhuoran;LI Zhi;YU Jiangong(School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China)

机构地区：[1]河南理工大学机械与动力工程学院,河南焦作454000

出　　处：《河南理工大学学报（自然科学版）》2023年第2期27-33,共7页Journal of Henan Polytechnic University（Natural Science）

基　　金：国家自然科学基金资助项目(5197518);河南省高校青年骨干教师培养计划项目(2018-GGJS-060)。

摘　　要：基于超声导波技术的锚杆无损检测对保障工程安全具有重要意义。利用解析勒让德多项式方法研究自由锚杆纵向超声导波传播和衰减特性,该方法克服了传统勒让德多项式方法因含有大量数值积分计算致使求解时间长的问题,计算效率得到极大提高。计算钢杆的纵向导波群速度和衰减,与已有文献结果比较,证明此方法的正确性;与传统多项式方法对比,揭示此方法的高效性。通过试验研究自由锚杆导波传播特性,测得导波群速度值,与理论结果进行比较。结果表明:自由锚杆L(0,3)-L(0,10)模态下的衰减最小值和群速度最大值均随模态阶数增大而增大,且衰减最小值与群速度最大值在同一频率处。导波衰减值与回波振幅之间存在对应关系,衰减值越小,端面回波幅值越大。The bolt nondestructive testing based on ultrasonic guided wave technology is of great signifi⁃cance to ensure the engineering safety.The propagation and attenuation characteristics of longitudinal ultra⁃sonic guided wave in a free bolt were studied in this paper,and the group velocity and attenuation of longi⁃tudinal guided wave were solved by the presented analytical Legendre polynomial method.The presented method could overcome the deficiency that the traditional Legendre method was time-consuming caused by a large number of numerical integral calculations,and the computational efficiency was greatly improved.The group velocity and attenuation of longitudinal guided wave in a steel bolt were calculated and compared with the literature’s ones to validate the presented method.Compared with the traditional polynomial method,the efficiency of the presented method was revealed.The guided wave propagation in a free bolt was also studied experimentally.The group velocity was measured and compared with the obtained theoreti⁃cal results.The results showed that for L(0,3)-L(0,10)modes of the free bolt,the minimum attenuation value and the maximum group velocity value appeared at the same frequency,and they increased with in⁃creasing the mode order.There was a relationship between the attenuation value and the echo amplitude.The smaller the attenuation value was,the larger the echo amplitude was.

关 键 词：自由锚杆 纵向超声导波 勒让德多项式方法 群速度 衰减 

分 类 号：TB302[一般工业技术—材料科学与工程]