Improved crack monitoring in structural concrete by combined acoustic emission and digital image correlation techniques

Abstract

Crack monitoring is crucial for safety, cost-effective design and maintenance of concrete structures. Most stand-alone crack monitoring techniques have some limitations in characterizing concrete cracking. Therefore, this article focuses on a combined use of acoustic emission and digital image correlation techniques for more effective monitoring of cracks in concrete structures at laboratory standard tests level. The combined methodology provides complimentary information from 'the ear' aided by the acoustic emission and from 'the eye' aided by the digital image correlation. This complimentary approach is applied herein to characterize the mechanical and damage behaviour of prestressed concrete sleepers that plays an important role in the structural mechanism of the railway structure. The obtained acoustic emission datasets were post-processed, in combination with digital image correlation and mechanical information, using parametric analyses to investigate progressive failure of the prestressed concrete sleepers under three-point bending at the rail seat and at the centre section. Digital image correlation clearly identified critical damage areas as a function of loading periods, while acoustic emission was capable of monitoring the damage process and revealed changes in the overall behaviour. It is demonstrated that the combined use of digital image correlation and acoustic emission can enhance practical applications and improve the understanding of concrete cracking behaviour.

Numerical and Experimental Study of Strain Localization in Notched Specimens of a Ductile Steel on Meso‐ and Macroscales

“…[35] Thus, in the present work, we employed the AE technique as a tool for monitoring temporal aspects of stress relaxation processes occurring at the tips of stress risers, as well as for distinguishing the major scale levels of plastic deformation and fracture. Using synchronized in situ video imaging and AE measurements offers a new promising way to characterization of defect dynamics under load for either deformation [39,40] or fracture processes, e.g., during fatigue crack growth [4,41] or fracture of composite materials [42] where AE increases sharply at the initiation of fracture while DIC experienced obvious difficulties because of low plasticity and multilayered structure of fiber reinforced composites. This is particularly important for the vicinity of notches, where local strain values can exceed significantly the average values in the specimen.…”

On the Numerical Modelling of Bond for the Failure Analysis of Reinforced Concrete

“…The numerical maximum principal strain contour plots representing crack patterns for the two approaches are compared to Digital Image Correlation (DIC) results for one of the experiments in Figures 14 and 15 for two stages at 0.8 and 9.5 ms, respectively, marked in Figure 13. DIC has been used in the past to record cracking processes in reinforced concrete structures [16,31] and has been shown to work for high speed processes [37]. In the present experimental study, a high [26,24].…”

Determination of yielding point by means a probabilistic method on acoustic emission signals for application to health monitoring of reinforced concrete structures

“…By using a proper array of sensors mounted on the RC structure, it is theoretically possible to determine the location of the AE source by analyzing the arrival times of the waves to each sensor . Similarly, AE testing can be used to study the initiation and growth of cracks in concrete in real time …”

“…3,4 Similarly, AE testing can be used to study the initiation and growth of cracks in concrete in real time. [5][6][7][8][9][10] It is known that "damage" is physical harm that impairs the value, usefulness, or normal function of something. Over the past few years, researchers have attempted to study the state of damage in RC structures using parameterbased AE monitoring techniques.…”