螺栓连接松动的导波监测技术综述

螺栓连接件使结构易于安装或拆卸,同时还可以承受较大的载荷,广泛应用于航空航天结构中。然而,螺栓在复杂服役环境中很容易发生松动,因此准确监测螺栓预紧力对于确保结构的可靠性和安全性具有重要意义。经过多年的发展,基于超声导波的结构健康监测方法逐渐成为螺栓连接松动监测的重要技术手段之一。对典型的螺栓预紧力导波监测方法进行了综述,包括导波能量耗散法、时间反转法、接触声学非线性法和混沌超声法等方法,介绍了这些方法的基本原理和发展现状。同时,通过实验将目前应用较多的导波能量耗散法、时间反转法进行了对比,结果表明时间反转法的监测灵敏度更高。

A Review on Bolt Preload Monitoring Using Guided Waves

Bolt joints are widely applied in aerospace engineering structures. Significant advantages of bolt joints are that they can be easily disassembled and the possibility to design for bearing large working load. However, in practical applications, preload loss in pre-tensioned bolts often happens. Reliable detection of bolt loosening is significant to ensure structural reliability and safety. In the past decades, the guided wave based structural health monitoring (SHM) methods have been developed for the detection of bolt loosening. In this paper, a few typical methods are reviewed, which involve wave energy dissipation based methods, time reversal guide wave methods, contact acoustic nonlinearity based methods and active chaotic ultrasonic excitation based methods. The basic principle and the applications of these methods are discussed. In addition, this paper presents an experimental comparison of wave energy dissipation and time reversal methods for the detection of bolt loosening in a lap-jointed specimen.