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Abstract Based on a series of creep tests with MTS815 rock mechanics test system and the acoustic emission(AE) monitoring system，the creep behavior of the Beishan granite is experimentally studied. A special attention is paid on the influence of temperature and stress level on the creep behavior and cracking process. The experiment data revealed that the creep process can be divided into three stages：the transient creep，the steady creep，and the accelerated creep. The rock failure is essentially related to the intensive accumulation and coalescence of microcracks during the accelerated creep stage. A consistent tendency between AE cumulative counts and volumetric creep strain is noticed. The variation of recorded AE events is found to be more sensitive to the occurrence of rock failure than the volumetric deformation. Under same confining pressure，it is indicated that the increase of temperature and stress level has quite limited affect on the total deformation before rock failure，while it may accelerate the cracking process，and consequently reduces the time to failure. The Beishan granite failed at a similar axial strain under the same confining pressure，of about 0.34%，0.54% and 0.71% under confining pressures of 2MPa，10MPa and 30MPa respectively.
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2015, Vol. 34 
