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.
Get full access to this article
View all available purchase options and get full access to this article.
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.
References
Ang, A.H-S., and Tang, W. H. (1975). Probability concepts in engineering, planning, and design, Vol. I, Wiley, New York.
Ang, A.H-S., and Tang, W. H. (1984). Probability concepts in engineering, planning, and design, Vol. II, Wiley, New York.
Christian, J. T., Ladd, C. C., and Baecher, G. B. (1994). “Reliability applied to slope stability analysis.” J. Geotech. Engrg., 120(12), 2180–2207.
Christian, J. T., Baecher, G. B. (1999). “Point estimate method as numerical quadrature.” J. Geotech. Geoenviron. Eng., 125(9), 779–786.
Duncan, J. M. (2000). “Factors of safety and reliability in geotechnical engineering.” J. Geotech. Geoenviron. Eng., 126(4), 307–316.
Greenwood, M. E., and Lang, D. C. (1990). “Vertical deflection of buried flexible pipes.” Proc., Symp. Buried Plastic Pipe Technology, STP 1093, ASTM, Philadelphia, 185–214.
Harr, M. E. (1987). Reliability-based design in civil engineering, McGraw-Hill, New York.
Hartley, J. D., and Duncan, J. M. (1987). “ and its variation with depth.” J. Transp. Eng., 113(5), 538–553.
Hornung, K., and Kittel, D. (1989). “Statik erduberdeckter Rohre.” Structural analysis of buried pipes, Bauverlag, GmbH, Berlin.
Howard, A. K. (1977). “Modulus of soil reaction values for buried flexible pipe.” J. Geotech. Engrg. Div., 103(1), 33–46.
Jeyapalan, J. K., and Boldon, B. A. (1986). “Performance and selection of rigid and flexible pipes.” J. Transp. Eng., 112(5), 507–524.
Kottegoda, N. T., and Rosso, R. (1998). Statistics, probability, and reliability for civil and environmental engineers, McGraw-Hill, New York.
Kreyszig, E. (1983). Advanced engineering mathematics, Wiley, New Delhi, India.
Masada, T. (2000). “Modified Iowa formula for vertical deflection of buried flexible pipe.” J. Transp. Eng., 126(5), 440–446.
Moser, A. P. (1990). Buried pipe design, McGraw-Hill, New York.
Nowak, A. S., and Collins, K. R. (2000). Reliability of structures, McGraw-Hill, New York.
Petroff, L. J. (1990). “Review of the relationship between internal shear resistance and arching in plastic pipe installations.” Proc., Symp. Buried Plastic Pipe Technology, STP 1093, ASTM, Philadelphia, 266–280.
Prevost, R. C., and Kienow, K. K. (1994). “Basics of flexible pipe structural design.” J. Transp. Eng., 120(4), 652–672.
Selig, E. T. (1990). “Soil properties for plastic pipe installations.” Proc., Symp. Buried Plastic Pipe Technology, STP 1093, ASTM, Philadelphia, 141–158.
Seshagiri Rao, R. (2004). “Response and reliability analysis of buried flexible pipes.” Ph.D. thesis, Dept. of Civil Engineering, Indian Institute of Science, Bangalore, India.
Seshagiri Rao, R., Sivakumar Babu, G. L., and Srinivasa Murthy, B. R. (2001). “Reliability based design of buried flexible pipes.” Proc., Advances in Pipeline Engineering and Construction, ASCE, Reston, Va.
Sivakumar Babu, G. L., and Seshagiri Rao, R. (2005). “Reliability measures for buried flexible pipes.” Can. Geotech. J., 42(2), 541–549.
Spangler, M. G., and Handy, R. L. (1973). Soil engineering, 3rd Ed., Harper and Row, New York.
U.S. Army Corps of Engineers (USACE. (1997). “Engineering and design introduction to probability an reliability methods for use in geotechnical engineering.” Engineering Circular No. 1110-2-547, USACE, Washington, D.C.
Watkins, R. K., and Spangler, M. G. (1958). “Some characteristics of the modulus of passive resistance of the soil—A study in similitude.” Proc., Highway Research Board, Vol. 37, 576–583.
Watkins, R. K., and Anderson, L. R. (1999). Structural mechanics of buried pipes, CRC, New York.
Whitman, R. V. (2000). “Organizing and evaluating uncertainty in geotechnical engineering.” J. Geotech. Geoenviron. Eng., 126(7), 563–593.
Information & Authors
Information
Published In
Journal of Transportation Engineering
Volume 132 • Issue 10 • October 2006
Pages: 829 - 836
Copyright
© 2006 ASCE.
History
Received: Jun 20, 2001
Accepted: Mar 30, 2006
Published online: Oct 1, 2006
Published in print: Oct 2006
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.