Research into stress-strain state of the mass under open pit with a change in the open-pit bottom width

Purpose. Studying the stress-strain state of rock mass under open pit, taking into account change in open-pit bottom width order to reveal geomechanical and determine safe parameters bridge. Methods. The peculiarities formation transition zone have been studied according methodology using numerical research methods geological strength index (GSI). Using this index, it is possible take fracturing, water cut, lithology other indicators, due which there a correct from sample strength. Findings. Based on modeling results, has determined that an increase leads decrease tensile stresses concentration arch pillar stope block. This, turn, positive effect bridge stability, is, probability collapse does not with bottom. Originality. For first time, dependence obtained horizontal σ3 distribution at stages expansion Akzhal Zinc-Lead Mine. This makes realistically predict changes depending Practical implications. When predicting determining parameters, reduce their destruction make timely management decisions conditions for mining reserves.