Numerical modeling of a talc mine exploitation using cemented backfilling

The Fontane mine (Rodoretto orebody located in Prali near Torino, north west of Italy) is a talc mine irregular vein orebody which is surrounded by a good quality rock mass, gneiss and micaschists). In the past few decades, this underground talc mine has been exploited by conventional cut and fill method using loose fill. Since the seventies, the backfilling has been operated downwards by use of cemented backfill. With this extraction approach, the orebody recovery and the safety of mining operations have been greatly improved. In a new mine section, a numerical modelling has been carried out to study the stress and displacement in the orebody and in the surrounding rock mass of the present condition and with the future development of the mine. The simulation was carried out with a 2D FEM model on relevant cross sections. The numerical modelling has been developed to evaluate how the mine deepening will affect the stability of the fill which was already put in place and of the embedding rock mass