Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.575711
Title: Acoustic emission analysis of prestressed concrete structures
Author: Elfergani, Hisham
Awarding Body: Cardiff University
Current Institution: Cardiff University
Date of Award: 2013
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Abstract:
This thesis examines the role of Acoustic Emission (AE) as a non-destructive testing (NDT) technique for prestressed and reinforced concrete structures. The work focuses on the development of experimental techniques and data analysis methods for the detection, location and assessment of AE from prestressed and reinforced concrete specimens. This thesis reveals that AE can be used to detect the onset of corrosion activity in wire in the interface between prestressed concrete and mortar as found in prestressed concrete pipes. Furthermore, this technique can be used to locate the corrosion activity on different size prestressed concrete samples. By correlation between three parameters of classical AE analysis techniques (traditional parameters), damage can be detected and located whilst the corrosion area, macro crack and crack propagation can be identified. However, it cannot classify the crack type. Different damage modes, including corrosion activity, micro/macro cracking formation, crack propagation and wire failure generate different types of AE signals with varying amplitudes and absolute energy emitted. A novel analysis approach has been used on composite materials (concrete, mortar and steel) to evaluate differing crack types by a combination of the classical acoustic emission analysis technique and advanced analysis Rise time / Amplitude (RA) and Average Frequency (AF), results proved the effectiveness of the developed techniques for damage detection and classification crack types. The relationship between RA value and AF value can be used to determine the crack area and classify it as either tensile crack type, other type (shear movement) or no crack. The results of the research have demonstrated that the AE technique is valid in larger scale monitoring and hence the potential for monitoring real structures such as prestressed concrete pipes. Use of Kernel Density Estimation Function (KDEF) provides improved visualisation of the data to represent clearly the RA/AF values. Key Words: Acoustic Emission, Corrosion, Reinforced Concrete, Prestressed Concrete, Micro and Macro Concrete Cracks, Crack classification, Source Location, Damage Assessment, Monitoring.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.575711  DOI: Not available
Keywords: TA Engineering (General). Civil engineering (General)
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