Abstract
Abstract
In earlier R&D works executed at IM SB RAS the optimal dose of the granite treatment with accelerated electrons was experimentally established. It equals 10 kGy, this doze causes weakening of granite strength under uniaxial compression from 68.33 to 35.08 MPa, deformation modulus reduces from 13.19 to 7.04 GPa. This pretreatment permits to lower the compressive energy of granite core disintegration from 7.68 to 3.06 J and the crushing energy from 700.42 to 470.88 J. Of specific technological importance is dynamics of chronological variations in mineral properties after pretreatment of minerals with accelerated electrons. The present research aim is to study chronological variations in properties of granite, conventionally associated with deposits of such valuable elements, as Au, Sn, W, Mo, Li, Be, Rb, Bi, etc. The complex experiments on granite revealed that after a granite specimen is subjected to the high-energy electron irradiation, the increase in an absorbed dose causes first reduction in P- and S-waves velocities, then P- and S-wave velocities are growing and later again slowing down. The established experimental regularities of variations in granite properties relate to granite imperfections, specified by memory of the study rock. The most substantial variations in P- and S-waves velocities in the pretreated granite-core specimens within time interval up to 5360 hours after the irradiation are recorded for the adsorbed dose equal to 10 kGy. The established increase in P- and S-waves velocities versus a time interval after granite-core treatment with the adsorbed dose of more than 10 kGy could indicate a reduction in number of available imperfections and a probable strengthening of the study mineral material. Scientific novelty of the present research concerns the determination of chronological variations in granite properties and the beneficial feasibility to use the mineral weakening effect of in mineral processing operations.