Failure loads analysis of corroded pipe repaired by composite material under tension and internal pressure

Abstract

Pipeline repair plays an important role in safe pipeline operation. Composite material repair technology has been widely used in pipeline repair due to its advantage of light weight and low cost. In this paper, the failure loads of repaired pipe with composite under tension and internal pressure are analysed by experiments, Finite Element Method (FEM) and theoretical method, and simple formula of failure loads is obtained based on theoretical analysis and verified by FEM and experiments. First, the tension experiment shows that debonding happens in the repaired pipe before its fracture, and then the debonding details are showed in FEM results considering the adhesive debonding criteria, finally a simple formula expression is obtained for the failure tension loads based on the analysis of interface stresses, and the results are almost consistent with the experimental method and FEM. Similarly, for the case under internal pressure, the blasting failure loads are obtained for the repaired pipe based on the theoretical analysis, which are consistent with FEM results.