L51646 Collapse of Offshore Pipelines Seminar Proceedings

The feasibility of laying offshore pipelines in deep waters, to 3000 feet and beyond, has been established by theoretical studies by a number of different individuals and organizations over the past several years. These various theoretical studies are now being tested and refined as pipelines and production facilities are being installed in ever-deeper waters. A pipeline failure in these great depths would be intolerable, among other reasons because of the great difficulty and exorbitant expense of performing a deepwater repair. A thorough understanding of the buckling and collapse behavior of pipe is, therefore, becoming ever more critical as these oil and gas production facilities get progressively deeper.

Recognizing a need for further research into the collapse behavior of pipe, Pipeline Research Council International, Inc. undertook in 1984 a three-phase program to develop a deeper understanding of basic pipe collapse phenomena. Phase I of this program (1984-1985) focused on the effects of imperfections on pipe collapse. This work was done in the laboratory of Professor Stelios Kyriakides at The University of Texas at Austin, and involved the testing of numerous small-scale steel and aluminum tubes. The Phase II program (1986-1987), also performed at The University of Texas, considered the effects of construction loads. The final Phase III program (1988-1989) was intended as a full-scale verification of the small-scale tests conducted in the previous two phases. This program was conducted at Stress Engineering Services in Houston under the direction of Dr. Joe Fowler, and consisted of Pure Collapse Tests of 16-inch Pipe (16 samples). Pressure vs. Tension Tests of 6 5/8-inch Pipe (18 samples), and Pressure vs. Bending Tests of 6 5/8-inch Pipe (18 samples).