Deformation Field and Acoustic Emission Characteristics of Weakly Cemented Rock under Brazilian Splitting Test

Abstract

Weakly cemented rocks are widely distributed in the Shendong Mining Area, and their mechanical properties and deformation characteristics have a significant influence on disaster prevention and the design of roadway excavation. This study investigated the evolution of the deformation field, acoustic emissions (AEs) and energy of four common weakly cemented rocks under Brazilian splitting test, and the relationship among the three parameters was discussed. The results show that the evolution of the coefficient of variation (C_v) in different rocks was similar and can be divided into two fast declining stages, a fluctuating rising stage and a sharply rising stage. There was a sudden increase in the cumulative AE energy before the peak strength was reached, which was positively correlated with the development of penetrating cracks. The evolution of C_v, growth rate of dissipated energy (G_d) and AE counts was consistent with the stress state, while there were some ‘non-corresponding points’ during the deformation and failure process. In addition, C_v, G_d and AE counts were more sensitive to deformation and failure characteristics than stress. The research findings provide basic parameters and a reference for predicting dynamic disasters in the Shendong Mining Area.