Design guidance and structural integrity of bonded connections in GRE pipes

Extensive research, involving a large programme of both experimental and numerical analyses, has been undertaken into the structural integrity of adhesively bonded GRE composite taper/taper pipe joints. Initial studies investigated the short-term static performance under various modes of loading and these were followed by studies of long-term creep performance. A significant element of the research was a study of the effect that defects in the adhesive bond have on the overall performance of the bonded joint-pipe system. The numerical analyses were correlated with the experimental data for validation of the computer simulations and failure predictions. The results of the research demonstrate the substantial defect tolerance of the bonded composite components. From the results it is possible to present guidelines for residual strength, deflection and the effects of defect size, as a function of pipe diameter, temperature and time. Such guidelines may be used at the initial design stage or to inform inspection and repair strategies.