Case Studies on Landslide Threats: Identification, Ground Modelling and Pipeline Structural Analysis

Abstract Geohazard management of pipelines in areas prone to landslides is an integrity threat that pipeline operators must address. The management process involves three key elements: (1) the identification of a developing hazard, (2) the evaluation of the nature of the threat and, (3) deciding on the most appropriate actions that are necessary to address the threat and to protect the pipeline. There are many available methods that can assist with the three parts of this process. However, the availability of multiple approaches can make it difficult to know what the most effective method is in terms of collecting the right data, making reliable predictions of pipeline integrity, or accurately monitoring future changes in integrity. Any deficiencies in the process can be wasted effort and cost at best, but could also result in failure, with adverse consequences for safety and the environment as well as severe financial penalties. In this paper, we present what we consider to be an effective and efficient management process for landslide threats to pipelines based on in-line inspection data integrated with detailed numerical modelling and structural analysis to evaluate pipeline integrity. In-line inspection provides factual data on the presence and effects of displacement loads on the pipeline as well as significant additional data on factors that control the structural capacity of the pipeline. The alignment of integrity calculations with measured inspection data enables the process to be validated and improves confidence in the predicted results. The process is comprehensively illustrated through a range of case studies. The significant potential of a novel inertial measurement unit technology (PipeDrift) for monitoring at an increased interval and reduced lead time is also covered.