Behaviour of Internal Replacement Pipe Systems Under Vehicular Traffic Loads

Abstract

Internal replacement pipe (IRP) systems are a new and emerging trenchless technology utilised for rehabilitating legacy gas and oil pipes with circumferential cracks or discontinuities. Effective design and analysis are required to ensure IRP systems will have reliable performance and durability against various types of loads, including lateral deformation and fatigue resulting from vehicular traffic loads. This study systematically investigated the static and fatigue behaviour of IRP systems in discontinuous host pipes under vehicular traffic loading using numerical modelling and simulation. The influence of critical design parameters, such as discontinuity width, repair thickness and repair material, internal pressure and level of bonding, on the behaviour of pipe repair systems was investigated. The study showed that the host pipe has the greatest impact on the lateral deformation for repaired systems with narrow discontinuity widths, whereas IRP is more influential on the repaired pipes with wider discontinuity widths. The discontinuity edge of the damaged pipe, where tensile stress is concentrated, has the greatest impact on the fatigue life of fully bonded IRP systems. Unbonded IRP systems have significantly higher fatigue life in comparison to fully bonded systems due to a large drop in the stress concentration at the discontinuity edges. The outcome of this study will provide valuable guidance for pipeline developers and designers, enabling improvement in safety, reliability, and effective implementation of IRP systems.

Techniques