Abstract The granite samples from Beishan of Gansu Province were tested on MTS815 Flex Test GT rock mechanics test system,including direct tensile test and indirect tensile test. The mechanical behaviors of granite were studied,and the acoustic emission(AE) was monitored by PCI–2 system. The test results showed that:the average value,the maximum and minimum values of tensile strength in direct tensile tests were greater than indirect tensile tests;the tensile strain of direct tensile tests was 6.03% of that of indirect tensile tests at the peak stress. Few AE signals were monitored for direct tensile tests before the loading stress was below 40% of the peak stress. When the loading stress was larger than 40% of the peak stress,AE counts and AE energy all increased. Especially,when it was close to the peak stress,AE events were the largest. For indirect tensile tests,the AE count rate during the full process was almost similar,and the energy release ratio at initial loading stage,e.g. less than 40% of the peak stress,was larger than the latter loading stage. Due to the effect of loading mode,the energy release ratio for indirect tensile tests was larger than that for direct tensile during the full failure process.
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Received: 05 November 2012
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