Publication details for Dr Will CoombsCoombs, W.M. & Crouch, R.S. (2011), Reuleaux plasticity: improving Mohr-Coulomb and Drucker-Prager, in Barends, F.B.J. Breedeveld, J., Brinkgreve, R.B.J., Korff, M. & van Paassen, L.A. eds, Geotechnical Engineering: New Horizons. Proceedings of the 21st European Young Geotechnical Engineers' Conference. Rotterdam, the Netherlands, IOS Press, 241-247.
- Publication type: Conference papers
- Keywords: geomaterials; computational plasticity; analytical stress return; Mohr-Coulomb; Drucker-Prager
Author(s) from Durham
The yielding of soil exhibits both a Lode angle dependency and a dependency on the intermediate principal stress. Ignoring these leads to a loss of realism in geotechnical analysis, yet neither of the widely used Mohr-Coulomb (M-C) or Drucker-Prager (D-P) models include both. This paper presents a simple pressure-dependent plasticity model based on a modified Reuleaux (mR) triangle which overcomes these limitations and yet (like the M-C and D-P formulations) allows for an analytical backward-Euler stress integration solution scheme. This latter feature is not found in more sophisticated (and computationally expensive) models. The mR deviatoric function is shown to provide a significantly improved fit to experimental data when compared with the M-C and D-P functions. Finite deformation finite-element analysis of the expansion of a cylindrical cavity is presented, verifying the use of the mR constitutive model for practical analyses.