Mechanical behavior of coal under true triaxial loading test connecting the effect of excavation- and mining-induced disturbances

Abstract In order to understand the mechanical behavior of a stope and analyse stress conditions surrounding rocks after ventilation shaft excavation abutment stresses top coal mining layout. situ uniaxial monitoring tests were performed field pressure evolution. Furthermore, variation concentration factor was studied using Tongxin Mine 8309 face TongMei Group, China, as case study. A loading model rock under excavation- mining-induced disturbances proposed, path experimental method designed investigate high excavation-damaged zone (HDZ), (EDZ), undisturbed (UZ). Moreover, characteristics failure in different zones site disturbance obtained mesoscopic analysis is carried out by acoustic emission test. The results indicated that strengths UZ, EDZ, HDZ samples declined gradually. volume UZ sample continuously expanded. However, volumes EDZ compressed first then shear bands presented all three resulted failure. cubic triaxial without considering produced higher less damage compared with true tests. used laboratory throughout could optimally reproduce process, which significantly safe efficient for deep resources.