Rafels, C.; Jaques, I.; Aliguer, I.; Carol, I.; Prat, P.; Lakshmikantha, R.M.; Segura, J. International Conference on Computational Plasticity p. 636-645 Data de presentació: 2017-09 Presentació treball a congrés
The in-situ stress field in rock masses is a key aspect when a numerical analysis of a rock mass is carried out in any area of geo-engineering, such as civil, mining, or Oil & Gas. A method for the numerical generation of the in-situ stress state in the FE context, based on Airy stress functions was previously introduced. It involves two steps: 1) an estimate of the stress state at each Gauss point is generated, and 2) global equilibrium is verified and re-balancing nodal forces are applied as needed. In this paper, new developments towards improving the accuracy of the stress proposal are discussed. A real application example has been used to illustrate the results achieved with the new implementation.
An accurate description of the in-situ stress field in a rock mass is crucial in different areas of geo-engineering such as: underground excavations, hydrocarbon extraction, CO2 storage, hydraulic fracture etc. In this paper, a novel methodology to numerically generate the in-situ stress state within the Finite Elements framework is presented. It involves two steps: 1) an estimate of the stress components is given for integration point of the discretization, and 2) global equilibrium is verified and re-balancing nodal forces are applied if needed. While the second step is a closed procedure based only on statics, the estimate of the in-situ stress field can be done in different ways in order to incorporate all the information available of the rock mass. In this paper, more traditional approaches are discussed and a new procedure based on the Airy stress function is described, in order to generate a stress state proposal at each Gauss point of the domain. Finally, the performance of different approaches is illustrated with a reservoir example.