Evaluation of Reinforced Concrete Structures with Magnetic Method and ACO (Amplitude-Correlation-Offset) Decomposition

Abstract

The magnetic method is one of the very few nondestructive testing (NDT) techniques that provide the possibility to conduct area tests of reinforced concrete (RC) structures in a fast, cheap, and straightforward way. This paper aims to present a new approach to the simultaneous identification of rebars’ diameter, alloy class, and thickness of the concrete cover tested with this method. Since rebars from different manufacturers may have different electromagnetic properties (standardization only for mechanical properties), preparing an effective and universal database is impossible. In this work, ACO decomposition is proposed, a new attributes extraction method designed to identify object parameters, even if it is impossible to collect a suitable training database (by pattern recognition and analysis of the deviation). Conducted tests prove that the ACO method enables accurate reflection of the waveform shape and limitation of attributes number to three or fewer (avoiding the curse of dimensionality). These properties, combined with the ability to analyze spatial components of magnetic induction (which only magnetic sensors provide), make the complex task of identification of three parameters more straightforward and the separation between the results received for different classes larger. This article presents the measurement results and the whole identification process.

In-Depth Steel Crack Analysis Using Photoacoustic Imaging (PAI) with Machine Learning-Based Image Processing Techniques and Evaluating PAI-Based Internal Steel Crack Feasibility

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Investigation of Carbon Fiber Reinforced Polymer Concrete Reinforcement Ageing Using Microwave Infrared Thermography Method

“…Different nondestructive testing techniques can be used to assess the quality of the cement-composite connection. Possible methods include the following: radiography, ultrasonic imaging, and thermovision and electromagnetic techniques [9][10][11][12][13][14][15]. Given the substantial size of the buildings under scrutiny, it is preferable to employ techniques that enable comprehensive assessment of extensive areas.…”

A Comparative Analysis of the Magnetization Methods Used in the Magnetic Nondestructive Testing of Reinforced Concrete Structures

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“…However, AMR technology offers higher bandwidth and measurement of negative values (polarization). Sensors of this kind also have a reset system that restores them to their original state after exceeding the measurement range [7,8,20,[27][28][29]. The high usefulness of the possibility of examining the spatial components of the magnetic field induction was proved in [8].…”