Lawrence Berkeley National Laboratory
Dilatancy Criteria for Salt Cavern Design: A Comparison Between Stress- and Strain-Based Approaches
- Author(s): Labaune, P
- Rouabhi, A
- Tijani, M
- Blanco-Martín, L
- You, T
- et al.
Published Web Locationhttps://doi.org/10.1007/s00603-017-1338-4
© 2017, Springer-Verlag GmbH Austria. This paper presents a new approach for salt cavern design, based on the use of the onset of dilatancy as a design threshold. In the proposed approach, a rheological model that includes dilatancy at the constitutive level is developed, and a strain-based dilatancy criterion is defined. As compared to classical design methods that consist in simulating cavern behavior through creep laws (fitted on long-term tests) and then using a criterion (derived from short-terms tests or experience) to determine the stability of the excavation, the proposed approach is consistent both with short- and long-term conditions. The new strain-based dilatancy criterion is compared to a stress-based dilatancy criterion through numerical simulations of salt caverns under cyclic loading conditions. The dilatancy zones predicted by the strain-based criterion are larger than the ones predicted by the stress-based criteria, which is conservative yet constructive for design purposes.