Alternative design of buried pipelines at active fault crossings using flexible joints

The use of "flexible joints" in buried high-pressure pipelines is examined herein as an effective design technique for the mitigation of Permanent Ground Displacement (PGD) effects due to fault activation. Pipeline joints that are available in the industry today are considered in connection with the needs of high-pressure pipelines in areas of seismic faults. The efficiency of this novel technique is examined through a series of parametric numerical analyses for both strike-slip and normal faults, while its applicability in common engineering problems is examined through an economic-technical comparison with more conventional techniques. It is concluded that the use of flexible joints provides a cost-efficient design method, that can drastically reduce pipeline strains for medium to large fault displacements.