This thesis examines the role of Acoustic Emission (AE) as a non-destructive\udtesting (NDT) technique for prestressed and reinforced concrete structures. The\udwork focuses on the development of experimental techniques and data analysis\udmethods for the detection, location and assessment of AE from prestressed and\udreinforced concrete specimens.\udThis thesis reveals that AE can be used to detect the onset of corrosion activity in\udwire in the interface between prestressed concrete and mortar as found in\udprestressed concrete pipes. Furthermore, this technique can be used to locate the\udcorrosion activity on different size prestressed concrete samples.\udBy correlation between three parameters of classical AE analysis techniques\ud(traditional parameters), damage can be detected and located whilst the corrosion\udarea, macro crack and crack propagation can be identified. However, it cannot\udclassify the crack type.\udDifferent damage modes, including corrosion activity, micro/macro cracking\udformation, crack propagation and wire failure generate different types of AE\udsignals with varying amplitudes and absolute energy emitted.\udA novel analysis approach has been used on composite materials (concrete,\udmortar and steel) to evaluate differing crack types by a combination of the\udclassical acoustic emission analysis technique and advanced analysis Rise time /\udAmplitude (RA) and Average Frequency (AF), results proved the effectiveness of\udthe developed techniques for damage detection and classification crack types.\udThe relationship between RA value and AF value can be used to determine the\udcrack area and classify it as either tensile crack type, other type (shear movement)\udor no crack.\udThe results of the research have demonstrated that the AE technique is valid in\udlarger scale monitoring and hence the potential for monitoring real structures\udsuch as prestressed concrete pipes.\udUse of Kernel Density Estimation Function (KDEF) provides improved\udvisualisation of the data to represent clearly the RA/AF values.\udKey Words: Acoustic Emission, Corrosion, Reinforced Concrete, Prestressed\udConcrete, Micro and Macro Concrete Cracks, Crack classification, Source\udLocation, Damage Assessment, Monitoring.
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