Authors: Vakili, A

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Vakili, A 2017, 'The improved unified constitutive model: a fine-tuned material model tailored for more challenging geotechnical conditions', in J Wesseloo (ed.), Deep Mining 2017: Proceedings of the Eighth International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 387-400,

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The improved unified constitutive model (IUCM) is a result of collating the most notable recent research works in the area of rock mechanics and extensive back-analysis of mining case histories together into a unified material model. This model has proven to provide a considerably more reliable prediction of rock mass behaviour than currently available modelling methods. Also, a transparent presentation of the model components and a detailed guideline for selection of input parameters make the IUCM an excellent candidate to potentially become a standard material model for numerical modelling in rock mechanics. This model can possibly improve the numerical modelling practices through improved reliability, simplifying application, standardising input selection, simplifying third party reviews and enabling regeneration by third parties. This paper first discusses the definitions, applications and limitations of conventional modelling methods. A practical and less theoretical introduction to the IUCM is then presented and finally, some case studies are shown where the predictive performance of this model is compared against the most commonly used material models.

Keywords: improved unified constitutive modelling (IUCM), advanced numerical modelling, constitutive model, material model

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