Stress–Strain Analysis of Buckling Failure in Phyllite Slopes

Buckling failure occurs in the open pit mines in the Quadrilátero Ferrífero of the State of Minas Gerais, Brazil. In this study, this failure mechanism is evaluated through stress–strain analysis, using the finite element software named Phase². Many representative hypothetical models of the slopes were created in order to reproduce the conditions in open pit mines, like their geometry and foliated joints with kinematic conditions for buckling failure. Elastic and plastic simulations have been done. Strength and deformability parameters, such as discontinuity stiffness and cohesion, as well as the in situ stress field, are analyzed in order to understand their influence in the buckling failure mechanism in the global open pit mine slopes excavated in phyllites. As studies about this problem are extremely rare, the present research brings important contributions to establish the basic conditions for this kind of failure.