TRUE TRIAXIAL EXPERIMENTAL STUDY ON ROCK WITH HIGH GEOSTRESS
高地应力下岩石的真三轴试验研究

The complicated evolvement of stress load, which is produced by excavating underground engineering under high stress conditions, is simulated through true triaxial experiment. Under the given loading method, the experimental results about new granite in Laxiwa show that the resilient deformation is found and acoustic emission counts rate is evidently enhanced when the minor principal stress is unloaded. The enhancing extent of acoustic emission counts rate increases with the intermediate principal stress. The constitutive relation is elasto-brittle. The peak value of strength increases with the intermediate principal stress; and the ratio of increasing value of limit strength and the intermediate principal stress decrease with the intermediate principal stress. The peak value of acoustic emission counts rate depends on stress state; and the amount of peak value is equal to that of major crack after failure. Finally, the failure mechanism is discussed.