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All Outputs (21)

Observations on Mohr-Coulomb plasticity under plane strain (2013)
Journal Article
Coombs, W., Crouch, R., & Heaney, C. (2013). Observations on Mohr-Coulomb plasticity under plane strain. Journal of Engineering Mechanics, 139(9), 1218-1228. https://doi.org/10.1061/%28asce%29em.1943-7889.0000568

Linear elastic-perfect plasticity using the Mohr-Coulomb yield surface is one of the most widely used pressure-sensitive constitutive models in engineering practice. In the area of geotechnical engineering a number of problems, such as cavity expansi... Read More about Observations on Mohr-Coulomb plasticity under plane strain.

A unique Critical State two-surface hyperplasticity model for fine-grained particulate media (2013)
Journal Article
Coombs, W., Crouch, R., & Augarde, C. (2013). A unique Critical State two-surface hyperplasticity model for fine-grained particulate media. Journal of the Mechanics and Physics of Solids, 61(1), 175-189. https://doi.org/10.1016/j.jmps.2012.08.002

Even mild compression can cause re-arrangement of the internal structure of clay-like geomaterials, whereby clusters of particles rotate and collapse as face-to-face contacts between the constituent mineral platelets increase at the expense of edge-t... Read More about A unique Critical State two-surface hyperplasticity model for fine-grained particulate media.

Plane-strain Mohr-Coulomb inelasticity (2012)
Presentation / Conference Contribution
Coombs, W., Crouch, R., & Heaney, C. (2012). Plane-strain Mohr-Coulomb inelasticity. In Z. J. Yang (Ed.),

Reuleaux plasticity: improving Mohr-Coulomb and Drucker-Prager (2011)
Presentation / Conference Contribution
Coombs, W., & Crouch, R. (2011). Reuleaux plasticity: improving Mohr-Coulomb and Drucker-Prager. In F. B. J. Barends, J. Breedeveld, R. B. J. Brinkgreve, M. Korff, & L. A. van Paassen (Eds.), Geotechnical engineering : new horizons, 21st European Young Geotechnical Engineers' Conference, 2011, Rotterdam ; proceedings (241-247). https://doi.org/10.3233/978-1-60750-808-3-241

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... Read More about Reuleaux plasticity: improving Mohr-Coulomb and Drucker-Prager.

On the f fields of inadmissible stress space (2011)
Presentation / Conference Contribution
Coombs, W. M., Crouch, R. S., & Augarde, C. E. (2011). On the f fields of inadmissible stress space. In E. Oñate, D. R. J. Owen, D. Peric, & B. Suárez (Eds.), Computational plasticity XI: fundamentals and applications

Unique Critical State Hyperplasticity (2011)
Presentation / Conference Contribution
Coombs, W. M., Crouch, R. S., & Augarde, C. E. (2011). Unique Critical State Hyperplasticity. In O. Laghrouche, A. EL Kacimi, P. Woodward, & G. Medero (Eds.), Proceedings of the 19th UK National Conference of the Association for Computational Mechanics in Engineering : 5-6 April 2011, Heriot-Watt University, Edinburgh (49-52)

Over the last 30 years there has been considerable interest in the extension of the modifed Cam Clay constitutive model to include anisotropic material behaviour. Many formulations have been proposed that allow the elliptical yield (or bounding) surf... Read More about Unique Critical State Hyperplasticity.

Non-associated Reuleaux plasticity: analytical stress integration and consistent tangent for finite deformation mechanics (2011)
Journal Article
Coombs, W., & Crouch, R. (2011). Non-associated Reuleaux plasticity: analytical stress integration and consistent tangent for finite deformation mechanics. Computer Methods in Applied Mechanics and Engineering, 200(9-12), 1021-1037. https://doi.org/10.1016/j.cma.2010.11.012

Analytical backward Euler stress integration is presented for a volumetrically non-associated pressure-sensitive yield criterion based on a modified Reuleaux triangle. This advances previous work on associated Reuleaux plasticity using energy-mapped... Read More about Non-associated Reuleaux plasticity: analytical stress integration and consistent tangent for finite deformation mechanics.

Algorithmic issues for three-invariant hyperplastic Critical State models (2011)
Journal Article
Coombs, W., & Crouch, R. (2011). Algorithmic issues for three-invariant hyperplastic Critical State models. Computer Methods in Applied Mechanics and Engineering, 200(25-28), 2297-2318. https://doi.org/10.1016/j.cma.2011.03.019

Implicit stress integration and the consistent tangents are presented for Critical State hyperplasticity models which include a dependence on the third invariant of stress. An elliptical deviatoric yielding criterion is incorporated within the family... Read More about Algorithmic issues for three-invariant hyperplastic Critical State models.

A C2 plasticity model for structural concrete (2010)
Journal Article
Li, T., & Crouch, R. (2010). A C2 plasticity model for structural concrete. Computers and Structures, 88(23-24), 1322-1332. https://doi.org/10.1016/j.compstruc.2008.10.009

Motivated by a requirement to provide a useable model to study the response of pre-stressed concrete nuclear reactor vessels, this paper (i) introduces a new three invariant C2 associated plasticity model, (ii) describes an efficient stress integrati... Read More about A C2 plasticity model for structural concrete.

Advances in meshless methods with application to geotechnics (2010)
Presentation / Conference Contribution
Heaney, C., Augarde, C., Deeks, A., Coombs, W., & Crouch, R. (2010). Advances in meshless methods with application to geotechnics. In T. Benz, & S. Nordal (Eds.), Numerical Methods in Geotechnical Engineering (239-244)

Finite element methods are well-established for modelling problems in geotechnics involving elasto-plastic constitutive models. However, meshless methods could offer some advantages for problems involving finite deformations as the mesh entanglement... Read More about Advances in meshless methods with application to geotechnics.

70-line 3D finite deformation elastoplastic finite-element code (2010)
Presentation / Conference Contribution
Coombs, W., Crouch, R., & Augarde, C. (2010). 70-line 3D finite deformation elastoplastic finite-element code. In B. T., & N. S. (Eds.), Numerical methods in geotechnical engineering : proceedings of the seventh european conference on numerical methods in geotechnical engineering, Trondheim, Norway, 2-4 June 2010 (151-156). https://doi.org/10.1201/b10551-28

Few freeware FE programs offer the capabilities to include 3D finite deformation inelastic continuum analysis; those that do are typically expressed in tens of thousands of lines. This paper offers for the first time compact MATLAB scripts forming a... Read More about 70-line 3D finite deformation elastoplastic finite-element code.

Reuleaux plasticity: analytical backward Euler stress integration and consistent tangent (2010)
Journal Article
Coombs, W., Crouch, R., & Augarde, C. (2010). Reuleaux plasticity: analytical backward Euler stress integration and consistent tangent. Computer Methods in Applied Mechanics and Engineering, 199(25-28), 1733-1743. https://doi.org/10.1016/j.cma.2010.01.017

Analytical backward Euler stress integration is presented for a deviatoric yielding criterion based on a modified Reuleaux triangle. The criterion is applied to a cone model which allows control over the shape of the deviatoric section, independent o... Read More about Reuleaux plasticity: analytical backward Euler stress integration and consistent tangent.

On the necessity for rotational yielding in anisotropic plasticity (2009)
Presentation / Conference Contribution
Coombs, W., Crouch, R., & Augarde, C. (2009). On the necessity for rotational yielding in anisotropic plasticity. In C. Sansour (Ed.), 17th UK Conference on Computational Mechanics (ACME-UK) (345-348)

Following suggestions by Masın [1], this paper re-examines whether the inelastic irrecoverable deformation of cohesive geomaterials can be adequately captured by Bounding Surface-type plasticity models with isotropic outer-surfaces (such as that prop... Read More about On the necessity for rotational yielding in anisotropic plasticity.

Coupled finite element–lattice Boltzmann analysis (2008)
Journal Article
Haslam, I., Crouch, R., & Seaïd, M. (2008). Coupled finite element–lattice Boltzmann analysis. Computer Methods in Applied Mechanics and Engineering, 197(51-52), 4505-4511. https://doi.org/10.1016/j.cma.2008.04.002

A coupled finite element (FE) and lattice Boltzmann (LB) numerical scheme to model the deformation of a porous solid through which fluid flows could offer an attractive solution strategy. As a precursor to a complete simulator, we review the two meth... Read More about Coupled finite element–lattice Boltzmann analysis.

Strains under transient hygro-thermal states in concrete loaded in multiaxial compression and heated to 250 °C (2008)
Journal Article
Petkovski, M., & Crouch, R. (2008). Strains under transient hygro-thermal states in concrete loaded in multiaxial compression and heated to 250 °C. Cement and Concrete Research, 38(4), 586-596. https://doi.org/10.1016/j.cemconres.2007.10.008

Previous experimental research has shown that the compactive strains in concrete subjected to a load-then-heat regime exceed those measured in heat-then-load tests under compression. This excess in strain is known as transient thermal creep or load-i... Read More about Strains under transient hygro-thermal states in concrete loaded in multiaxial compression and heated to 250 °C.

Apparatus for testing concrete under multiaxial compression at elevated temperature (mac2T) (2006)
Journal Article
Petkovski, M., Crouch, R., & Waldron, P. (2006). Apparatus for testing concrete under multiaxial compression at elevated temperature (mac2T). Experimental Mechanics, 46(3), 387-398. https://doi.org/10.1007/s11340-006-7463-8

This paper describes a new test facility for determining material mechanical properties of structural concrete. The novel facility subjects 100 mm cubic concrete specimens to true multiaxial compression (σ1 ≠ σ2 ≠ σ3) up to 400 MPa at temperatures of... Read More about Apparatus for testing concrete under multiaxial compression at elevated temperature (mac2T).

Modeling the dynamics of fermentation and respiratory processes in a groundwater plume of phenolic contaminants interpreted from laboratory-to field-scale (2005)
Journal Article
Watson, I., Oswald, S., Banwart, S., Crouch, R., & Thornton, S. (2005). Modeling the dynamics of fermentation and respiratory processes in a groundwater plume of phenolic contaminants interpreted from laboratory-to field-scale. Environmental Science and Technology, 39(22), 8829-8839. https://doi.org/10.1021/es0507970

A biodegradation model with consecutive fermentation and respiration processes, developed from microcosm experiments and simulated mathematically with microbial growth kinetics, has been implemented into a field-scale reactive transport model of a gr... Read More about Modeling the dynamics of fermentation and respiratory processes in a groundwater plume of phenolic contaminants interpreted from laboratory-to field-scale.

Advantages of using adaptive remeshing and parallel processing for modelling biodegradation in groundwater (2005)
Journal Article
Watson, I., Crouch, R., Bastian, P., & Oswald, S. (2005). Advantages of using adaptive remeshing and parallel processing for modelling biodegradation in groundwater. Advances in Water Resources, 28(11), 1143-1158. https://doi.org/10.1016/j.advwatres.2005.01.003

Biodegrading plumes in groundwater are often typified by relatively reactive zones around the fringes and less reactive zones in the core. A high degree of refinement is required at the fringes if a model is to be of use in improving the conceptual u... Read More about Advantages of using adaptive remeshing and parallel processing for modelling biodegradation in groundwater.