Remote nondestructive evaluation technique using infrared thermography for fatigue cracks in steel bridges

Abstract

Long‐standing infrastructure is subject to structural deterioration. In this respect, steel bridges suffer fatigue cracks, which necessitate immediate inspection, structural integrity evaluation or repair. However, the inaccessibility of such structures makes inspection time consuming and labour intensive. Therefore, there is an urgent need for developing high‐performance nondestructive evaluation (NDE) methods to assist in effective maintenance of such structures. Recently, use of infrared cameras in nondestructive testing has been attracting increasing interest, as they provide highly efficient remote and wide area measurements. This paper first reviews the current situation of nondestructive inspection techniques used for fatigue crack detection in steel bridges, and then presents remote NDE techniques using infrared thermography developed by the author for fatigue crack detection and structural integrity assessments. Furthermore, results of applying fatigue crack evaluation to a steel bridge using the newly developed NDE techniques are presented.

Towards Automated Tracking of Initiation and Propagation of Cracks in Aluminium Alloy Coupons Using Thermoelastic Stress Analysis

“…Therefore, non-destructive methods to detect the initiation and propagation of these cracks are necessary in order to allow monitoring and remedial action to be undertaken. This monitoring must often be undertaken in areas which are difficult to access, or during service [1]. Methods which are currently applied include visual inspection, placement of strain gauges, magnetic particle testing, ultrasound, digital image correlation (DIC), and electronic speckle pattern interferometry (ESPI) [1][2][3].…”

“…This monitoring must often be undertaken in areas which are difficult to access, or during service [1]. Methods which are currently applied include visual inspection, placement of strain gauges, magnetic particle testing, ultrasound, digital image correlation (DIC), and electronic speckle pattern interferometry (ESPI) [1][2][3]. Each of these have drawbacks, for example, strain gauge measurements require prior knowledge of expected crack sites as their use only allows localised data collection.…”

Digital energy grade‐based approach for crack path prediction based on 2D X‐ray CT images of geomaterials

“…Therefore, crack path prediction is crucial in engineering practices. Various methods can be applied to study cracking characteristics and failure mechanisms and to simulate the evolution process of cracks, including the infrared imaging technique, the finite element method, the extended finite element method, the peridynamics, the general particle dynamics, the phase‐field method with the arc‐length method and level‐set techniques, and the burgeoning computed tomography techniques . For example, Miranda et al predicted the propagation life of cracks in generic 2D structural components using a cost‐effective two‐phase methodology; Geißler et al estimated discrete crack paths using the adaptive modified nodal coordinates and element boundary combined with a finite element framework; Haeri et al investigated the crack initiation, propagation, and coalescence process of brittle materials using the higher‐order displacement discontinuity method and Scanning electron microscope (SEM) images and studied the crack propagation mechanism of precracked rock‐like materials; Azevedo et al combined a natural neighbor radial point interpolation method with the meshless method to predict the crack path of materials and extended it to fracture mechanics; Wick et al proposed a rate‐dependent formulation to solve the crack propagation problems in elasticity and elastoplasticity conditions in the phase field framework; Zhao et al proposed a new data analysis method to investigate the morphological changes in a single fracture of rocks under different confining pressures based on transient pulse tests and 3D laser scanning; and Martínez et al discussed fretting fatigue crack trajectory using the extended finite element method (XFEM) method.…”

Virtual structural health monitoring and remaining life prediction of steel bridges

“…Implementing accurate long-term SHM systems for bridges has been increasingly recognized in Canada (Desjardins et al 2006;Mufti 2002;Cheung et al 1997;Clarke 2014;Ghodoosipoor 2013), the USA (Saberi et al 2016), Europe (Farreras-Alcover et al 2016;Chellini et al 2014;Dudás et al 2015;Alampalli 2012;Cross et al 2013), Japan (Sakagami 2015;Watanabe et al 2014), China (Yan et al 2016;Guo Tong et al 2008), and elsewhere. Inaudi (2010) has conducted an overview of 40 bridge monitoring projects carried out in the period, 1996-2010, in 13 different countries including Austria, Belgium, Canada, Croatia, France, Germany, Italy, Japan, Luxembourg, Russia, Sweden, Switzerland, Taiwan and the USA.…”