Material model for soil and applications

This chapter deals with the development of a realistic material model for the simulation of the mechanical behavior of granular soil. The material model is formulated in the framework of multi-surface viscoplasticity, involving a Mohr-Coulomb criterion for the simulation of compressive loading and a tension-cut-off for capturing the response of soil under tensile loading. Whereas the tension-cut-off is assumed to be ideally-plastic, friction harding is considered in the Mohr-Coulomb criterion. The commonly observed change in the dilational behavior of granular soil during plastic deformations is accounted for by a non-associative flow rule. After presentation of the algorithmic formulation of the proposed material model, its applicability for investigations of real-life structures is demonstrated by means of numerical analyses of two Austrian tunnels, focusing on (i) the effect of ground improvement by means of jet grouting and (ii) the safety of tunnels under fire load.

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