Abstract

The United States economy is heavily dependent upon a vast network of pipeline systems to transport and distribute the nation's energy resources. As this network of pipelines continues to age, monitoring and maintaining its structural integrity remains essential to the nation's energy interests. Numerous pipeline accidents over the past several years have resulted in hundreds of fatalities and billions of dollars in property damages. These accidents show that the current monitoring methods are not sufficient and leave a considerable margin for improvement. To avoid such catastrophes, more thorough methods are needed. As a solution, the research of this thesis proposes a structural health monitoring (SHM) system for pipeline networks. By implementing a SHM system with pipelines, their structural integrity can be continuously monitored, reducing the overall risks and costs associated with current methods. The proposed SHM system relies upon the deployment of macro-fiber composite (MFC) patches for the sensor array. Because MFC patches are flexible and resilient, they can be permanently mounted to the curved surface of a pipeline's main body. From this location, the MFC patches are used to monitor the structural integrity of the entire pipeline. Two damage detection techniques, guided wave and impedance methods, were implemented as part of the proposed SHM system. However, both techniques utilize the same MFC patches. This dual use of the MFC patches enables the proposed SHM system to require only a single sensor array. The presented Lamb wave methods demonstrated the ability to correctly identify and locate the presence of damage in the main body of the pipeline system, including simulated cracks and actual corrosion damage. The presented impedance methods demonstrated the ability to correctly identify and locate the presence of damage in the flanged joints of the pipeline system, including the loosening of bolts on the flanges. In addition to damage to the actual pipeline itself, the proposed methods were used to demonstrate the capability of detecting deposits inside of pipelines. Monitoring these deposits can prevent clogging and other hazardous situations. Finally, suggestions are made regarding future research issues which are needed to advance this research. Because the research of this thesis has only demonstrated the feasibility of the techniques for such a SHM system, these issues require attention before any commercial applications can be realized. Document type: Report

Abstract

The European objective of a modal shift of freight transports to railways will require extensive upgrading of"br" existing railway lines. This is due to the fact that very few dedicated freight railways are currently being built and"br" existing lines were built for traffic demands at the time of construction. A transition to increased and enhanced"br" railway freight operations can therefore be costly and complicated. To minimize negative effects, a guideline for"br" upgrading was developed within the Capacity4Rail project. The current paper presents the major findings from"br" this guideline. In particular, it outlines different upgrading possibilities and their implications, and details"br" structured approaches to upgrading analyses. Setting out from the Capacity4Rail handbook, the current paper"br" discusses possibilities for upgrading of substructures, bridges, tunnels, and the track structure. In these areas, an"br" overview of challenges and possibilities is presented together with examples of experience from operational"br" upgrading. The paper concludes that freight line upgrading using a more streamlined approach, as outlined in the"br" guideline, is a necessity if EU objectives on modal shifts in transportation are to be met. Further, it demonstrates"br" why a political drive is necessary to increase efforts to upgrade freight lines.