A Novel steel pipe joint for enhancing pipeline seismic resilience i: Development and validation

Abstract

During the last four years, an extensive experimental project has been launched to determine the structural performance of lap welded joints under ground-induced deformations, mainly due to severe seismic events. The research consists of full-scale physical experiments, supported and validated by numerical finite element simulations. Previous experimental results indicated a remarkable strength and deformation capacity of the standard lap welded joints without loss of water containment. The latest phase of the research focuses on the behavior, analysis, and design of a new seismic resistant lap welded joint. Results of a series of additional full-scale experiments on the structural performance of the new lap welded joint under strong axial and bending loading conditions are presented, supported by finite element simulations. The new lap welded joint comprises the standard lap weld configuration with an additional small geometric projection introduced at a specific location near the field applied fillet weld, resulting in consistent buckling of the steel pipe cylinder and not the lap weld joint, during extreme loading. The proposed joint, referred to as Seismic Resilient joint or SR-joint (patent pending), offers an efficient, reliable, yet economical solution for welded joints in steel water pipelines constructed in seismic areas. © ASCE.