Failure analysis of (±55°)₉ filament-wound GRE pipes using acoustic emission technique

In the present study, relevant tensile tests are conducted in ring specimens for determination of apparent hoop tensile strength of an industrial (±55°)₉ filament-wound GRE pipe. To characterize the different failure mechanisms of these specimens, acoustic emission (AE) technique is used. The acoustical parameters including the energy, the accumulated energy, the amplitude, and the ratio of rise time to peak amplitude (rise angle or RA), as well as the ratio of number of counts to duration (average frequency or AF) are analyzed during the tests. The ability of each acoustical parameter in describing the failure mechanisms is discussed and comprised with the available performed studies. A comparison between mechanical response and analyzed AE signals is made to correlate each stage of loading to its associated failure mechanism. A scanning electron microscope (SEM) is also used to verify the obtained results from the analysis of acoustical parameters.