Gjerapic, G & Thompson, TW 2008, 'Evaluation of Salt Cavern Closure Via FEM Code PLAXIS ', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium
, Australian Centre for Geomechanics, Perth, pp. 487-495, https://doi.org/10.36487/ACG_repo/808_65
Determining suitable operating pressures is important when developing deep storage cavities in salt formations due to continuous reduction in the cavern storage capacity caused by creep of the surrounding rock mass. Optimisation for long-term cavern performance typically requires numerical modelling to evaluate different geometries, operating pressures, account for variations in stratigraphy and material properties, and to develop closure predictions over relatively long periods. Commercially available numerical models offer different interface environments and solution methods resulting in varying levels of effort required for model set-up and execution. Models employing a simple graphical user interface and stable fast-execution algorithms are often preferred in the early stages of cavern design.
This paper discusses the implementation and numerical performance of creep algorithms using the finite element model (FEM) code PLAXIS. Constitutive models were implemented to evaluate salt cavern closure at a proposed gas storage facility in southern Arizona, USA. The PLAXIS results were verified against one-dimensional analytical solutions and compared to the finite difference code FLAC™ for a three-dimensional case scenario considering axisymmetric cavern closure.
Brinkgreve, R.B.J. (2002) Plaxis version 8 material models manual, A.A. Balkema Publishers, Netherlands.
Goodman, R.E. (1980) Introduction to rock mechanics, John Wiley and Sons, New York.
Handin, J. and Hager, R.V. Jr. (1957) Experimental study of the strength of sedimentary rocks under confining pressure: tests at room temperature on dry samples, American Association of Petroleum Geologists Bulletin, Vol. 41, No. 1, pp. 1–50.
Hansen, F.D., Kirby, D.M. and Senseny, P.E. (1981) Elasticity and strength of ten natural rock salts, First Conference on the Mechanical Behavior of Salt, Pennsylvania State University, November 9–11.
Itasca Consulting Group, Inc. (2005) FLAC™ – Fast Lagrangian Analysis of Continua – optional features, user’s manual for version 5.0, Minneapolis Minnesota, USA.
Perzyna, P. (1966) Fundamental problems in viscoplasticity, Advances in Applied Mechanics, Vol. 9, Academic, New York, pp. 343–377.
RESPEC (2004) Disposal room calculations with alternative true waste models, Report RSI-1783 prepared for Sandia National Laboratories, June.