Back analysis of block falls in underground panel cave excavations: The experience in panel caving at El Teniente Mine-Codelco Chile

摘要

In this paper are introduced four cases of block failure from Reservas Norte Sector, at El Teniente Mine. Block stability analysis are carried out using specialized software packages, with the purpose of obtaining geometrical characterization of key-blocks. An hypothesis of failure controlled principally by an unfavorable induced stress ratio is introduced, and a sensibility analysis is carried out - taking the geometric information of fallen blocks - to draft the induced stress ratio that governs key-block fall. Finally, one of the case studies is analyzed with more detail to find out condition of stresses (stress ratio and stress magnitude) that determine wedge failure.