Implementação elastoplástica do critério de ruptura de Hoek-Brown para maciço rochoso.

Abstract

This research is developed in the context of rock mechanics regarding to design of excavations in rock by mean of numerical method. Hoek-Brown failure criterion for analysis of stability in rock masses excavations is implemented in elastoplastic system by means of OWEN & HINTON finite elements program coded in FORTRAN language. The correlation between Mohr-Coulomb and Hoek-Brown failure criteria are analyzed, confirming the Andrade Lima [3] implementation using tangents to Hoek-Brown envelopes, where the relationship between c, <(>, oc , and p resistance parameters of Mohr-Coulomb criterion with s, m, and ac from Hoek- Brown criterion are established. It has also been analyzed the possibility of estimating rock masses resistance properties from laboratory properties of intact rock, by means of rock masses classifications systems or scale effects curves. The correlation between parameters m and s in (<n , G3) plane with A and B in (T , a) plane from Hoek-Brown criterion is analyzed. The implementation of Hoek-Brown criterion in elastoplastic system is validated by means of sample problems. The results have showed very close agreement with the tangent approach. It is developed a code for plotting a three dimensions yielding surfaces of Mohr-Coulomb and Hoek-Brown by mean of Matlab software.