Lateral Load-Displacement Behavior of Pipelines in Unsaturated Sands
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 142, Issue 11
Abstract
Conventional design guidelines for buried pipelines are based on the assumption that soil is either dry or fully saturated. In unsaturated soils, such an assumption may lead to underestimation of load from externally imposed ground movement. Such loads are generated because the water meniscus between soil particles creates an additional interparticle force due to suction, which in turn makes the soil stiffer and stronger. This paper presents a methodology for predicting lateral loads on pipelines in unsaturated sandy soils by investigating soil-pipe interaction with full-scale tests and characterizing unsaturated soil behavior with properties from triaxial tests. A constitutive model was developed, and finite-element (FE) simulations were performed and compared with the full-scale test results to validate the modeling process. Additional FE simulations were conducted to assess the maximum lateral load on pipelines buried in different Class II unsaturated sands. The full-scale tests and FE simulations show that increased strength and stiffness associated with soil suction increases lateral loads on pipelines and thus need to be considered when designing pipelines for externally imposed ground movement. The modeling procedures and results can be used to predict lateral loads on underground pipelines subjected to construction and earthquake-induced ground movements, landslides, and subsidence. Because most pipelines are buried in unsaturated soil, the results have widespread relevance in design and construction.
Get full access to this article
View all available purchase options and get full access to this article.
References
ABAQUS version 6.8 [Computer software]. Dassault Systèmes, Providence, RI.
Alonso, E., Gens, A., and Josa, A. (1990). “A constitutive model for partially saturated soils.” Geotechnique, 40(3), 405–430.
Arya, L. M., and Paris, J. F. (1981). “A physicoempirical model to predict soil moisture characteristics from particle-size distribution and bulk density data.” Soil Sci. Soc. Am. J., 45(6), 1023–1030.
ASCE. (1984). “Guidelines for the seismic design of oil and gas pipeline systems.” Gas and Liquid Fuel Lifelines of the ASCE Technical Council on Lifeline Earthquake Engineering, Reston, VA.
ASTM. (2011). “Standard practice for underground installation of thermoplastic pipe for sewers and other gravity-flow application.” D2321-11, West Conshohoken, PA.
Been, K., and Jefferies, M. G. (1985). “A state parameter for sands.” Geotechnique, 35(2), 99–112.
Bishop, A. W. (1959). “The principles of effective stress.” Tecnisk Ukeblad, 106(39), 859–863.
British Standards Institution. (1990). “Methods of test for soils for civil engineering purposes. Shear strength tests (effective stress).” BS 1377–8, London.
Cheong, T. P. (2006). “Numerical modelling of soil-pipeline interaction.” Ph.D. thesis, Univ. of Cambridge, Cambridge, U.K.
Fern, J., Soga, K., and Robert, D. J. (2014a). “Shear strength and dilatancy of partially saturated sand in direct shear tests.” Proc., TC105 ISSMGE Int. Symp. on Geomechanics from Micro to Macro, Taylor & Francis, London, 1391–1396.
Fern, J., Soga, K., Robert, D. J., and Sakanoue, T. (2014b). “Shear strength and dilatancy of unsaturated silica sand in triaxial compression tests.” Proc., 14th Int. Conf. of Int. Association for Computer Methods and Recent Advances in Geomechanics, Taylor & Francis, London, 535–540.
François, B., and Laloui, L. (2008). “ACMEG-TS: A constitutive model for unsaturated soils under non-isothermal conditions.” Int. J. Numer. Anal. Methods Geomech., 32(16), 1955–1988.
Honegger, D., and Nyman, D. J. (2004). “Guidelines for the seismic design and assessment of natural gas and liquid hydrocarbon pipelines.”, Pipeline Research Council International, Houston.
Jefferies, M. G. (1993). “Nor-Sand: A simple critical state model for sand.” Geotechnique, 43(1), 91–103.
Jung, J., O’Rourke, T. D., and Olson, N. A. (2013). “Lateral soil-pipe interaction in dry and partially saturated sand.” J. Geotech. Geoenviron. Eng., 2028–2036.
Loret, B., and Khalili, N. (2002). “An effective stress elastic-plastic model for unsaturated porous media.” Mech. Mater., 34(2), 97–116.
Marshall, T., and Holmes, J. (1988). Soil physics, 2nd Ed., Cambridge University Press, Cambridge, U.K.
Matsuoka, H., and Nakai, T. (1985). “Relationship among Tresca, Mises, Mohr-Coulomb and Matsuoka-Nakai failure criteria.” Soil Found., 25(4), 123–128.
Olson, N. (2009). “Soil performance for large-scale soil-pipeline tests.” Ph.D. thesis, Cornell Univ., Ithaca, NY.
O’Rourke, T. D., et al. (2008). “Geotechnics of pipeline system response to earthquakes.” Proc., Geotechnical Earthquake Engineering and Soil Dynamics IV, ASCE, Reston, VA.
O’Rourke, T. D. (2010). “Geohazards and large geographically distributed systems.” Geotechnique, 60(7), 503–504.
O’Rourke, T. D., Jung, J., and Argyrou, C. (2015). “Underground infrastructure response to earthquake-induced ground deformation.” Proc., 6th Int. Conf. on Earthquake Geotechnical Engineering, International Society for Soil Mechanics and Found Engineering, ISSMGE.
Robert, D. J. (2010). “Soil-pipeline interaction in unsaturated soils.” Ph.D. thesis, Univ. of Cambridge, Cambridge, U.K.
Robert, D. J., and Soga, K. (2013). “Soil–pipeline interaction in unsaturated soils.” Chapter 13, Mechanics of unsaturated geomaterials, L. Laloui, ed., Wiley, London, 303–325.
Robert, D. J., Soga, K., and O’Rourke, T. D. (2016). “Pipelines subjected to fault movement in dry and unsaturated soils.” Int. J. Geomech., C4016001.
Schofield, A., and Wroth, P. (1968). Critical state soil mechanics, 2nd Ed., McGraw-Hill, London.
Turner, J. E. (2004). “Lateral force-displacement behavior of pipes in partially saturated sand.” M.S. thesis, Cornell Univ., Ithaca, NY.
Yimsiri, S., Soga, K., Yoshizaki, K., Dasari, G. R., and O’Rourke, T. D. (2004). “Lateral and upward soil-pipeline interactions in sand for deep embedment conditions.” J. Geotech. Geoenviron. Eng., 830–842.
Information & Authors
Information
Published In
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Jan 19, 2015
Accepted: Jan 22, 2016
Published online: Jun 17, 2016
Published in print: Nov 1, 2016
Discussion open until: Nov 17, 2016
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.