Reliability Analysis of Deflection of Buried Flexible Pipes
Publication: Journal of Transportation Engineering
Volume 132, Issue 10
Abstract
The in situ behavior of buried flexible pipes is considerably influenced by uncertainties in external load, pipe, and soil properties. To take care of the uncertainties, while the conventional design methodology incorporates conservative factors of safety, it is desirable that these aspects of variability be incorporated in the design. In this paper, uncertainties in calculation of pipe deflection are reviewed. Soil stiffness and load are considered as random variables. Reliability assessment of deflection of a typical pipe section with typical soil properties is conducted using the point estimate method with respect to two reliability measures, central factor of safety and safety margin. Within the framework of analysis, results show that for flexible pipes, the conventional tolerable deflection limit of 5% of diameter of the pipe with respect to a factor of safety of 4 is conservative.
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Acknowledgments
The writers thank the reviewers for their critical comments. The work reported in this paper is part of a research project on reliability analysis of buried pipes, sponsored by the Department of Science and Technology, Government of India, New Delhi. Financial assistance of DST is gratefully acknowledged.
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© 2006 ASCE.
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Received: Jun 20, 2001
Accepted: Mar 30, 2006
Published online: Oct 1, 2006
Published in print: Oct 2006
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