Steel Corrosion in Magnesia-Phosphate Cement Concrete Beams

Abstract

The acoustic emission (AE) technique was employed to investigate the corrosion-induced deterioration of steel-reinforced magnesia-phosphate cement (MPC) concrete beams under the coupling effect of loading and accelerated chloride diffusion. A cement-based piezoelectric sensor was used for AE detection owing to its high sensitivity and good compatibility with the concrete matrix. Power spectral density analysis and continuous wavelet transform were used to process the detected AE signals. It was found that the average frequency shift was closely related to the damage accumulation level in the reinforced MPC concrete beams. Based on the frequency characteristics of the detected AE signals during wet-dry cycles, the corrosion-induced degradation process of MPC beams was divided into three stages, from micro-cracking to localised macro-crack propagation. Wavelet analysis revealed the energy density distribution of the AE waveform, which was used to differentiate signal features between reinforcement corrosion and concrete cracking. In addition, comparisons in terms of the accumulated AE event number and half-cell potentials showed that MPC and OPC concrete had comparable corrosion inhibition capabilities.

Department(s)

Civil, Architectural and Environmental Engineering

Keywords and Phrases

Beams and Girders; Cements; Concrete Beams and Girders; Concretes; Corrosion; Cracks; Power Spectral Density; Reinforcement; Spectral Density; Wavelet Analysis; Wavelet Transforms; Acoustic Emission Techniques; Continuous Wavelet Transform; Corrosion-induced Deterioration; Energy Density Distributions; Frequency Characteristic; Magnesia Phosphate Cements; Power Spectral Density Analysis; Reinforcement Corrosion; Acoustic Emission Testing; Durability-Related Properties

International Standard Serial Number (ISSN)

0024-9831

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2017 ICE Publishing, All rights reserved.

Publication Date

01 Jan 2017

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