Behavior of Cold Bend Pipes under Bending Loads
Publication: Journal of Structural Engineering
Volume 137, Issue 5
Abstract
Ground movement along a buried pipeline often places the line in net compression. The local buckling resistance at cold bends is less than at straight sections, and hence, local buckling tends to occur at bends. Correspondingly, this full-scale testing program was conducted to investigate the local and global load-deformation relationships for seven cold bend pipes under applied loads. The specimens were loaded under bending, axial load, and internal pressure until local buckling occurred, and their curvatures were subsequently increased to establish their postbuckling behaviors. It was demonstrated though these tests that the buckling strain of the cold bend pipes was considerably lower than a straight pipe and that the presence of internal pressure exhibited a predominant role on the specimens load-deformation behaviors. It was also established that the behavior of the specimens was relatively unaffected by the bending methods that were employed during cold bending.
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Acknowledgments
This research project was conducted with the financial assistance from SNAM Rete Gas Ltd. and Tokyo Gas Ltd. In addition to their valuable financial contributions, several members of the industrial sponsor companies provided greatly appreciated technical assistance to this project. In particular, we would like to thank M. Como and E. Cerelli from SNAM Rete Gas Ltd., along with K. Yoshizaki and N. Fukada from Tokyo Gas Ltd. We would also like to acknowledge the technical assistance of K. Adams and S. Adeeb from TransCanada Pipelines Ltd., along with the much appreciated expertise of D.W. Murray from the University of Alberta.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 137 • Issue 5 • May 2011
Pages: 571 - 578
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Feb 1, 2008
Accepted: Mar 10, 2010
Published online: Mar 12, 2010
Published in print: May 1, 2011
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