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Abstract When rock material is loaded，the deformation and internal fracture will be induced，and then part of the stored energy will be released in the form of stress wave，which triggers the acoustic emission(AE) phenomenon. Based on triaxial compression tests and AE test，the relationship between AE characteristics and mechanical parameters of the monzonite granite taken from Linglong gold mine is investigated. The main conclusions can be drawn as follows：(1) When rock sample is under triaxial compression，the AE characteristics basically conforms to the four stage of rock failure process，however，the compaction stage (closure of microcracks) is not shown clearly due to the compaction effect of confining pressure on the tested rock material. (2) By analyzing the influence of confining pressure on the memory effect of rock material，it is indicated that，under relatively low confining pressure，the Kaiser effect distinctiveness decreases with the increase of axial stress level while the Felicity effect distinctiveness shows a contrary result. However，with increasing confining pressure，the Kaiser effect distinctiveness becomes increasing and the Felicity effect distinctiveness decreases. (3) It is more suitable to employ triaxial compression tests for in-situ stress measurement with AE，because triaxial compression tests can eliminate the error induced by different stress environments and indistinctions of Kaiser effect under high confining pressure level，which makes the measured value more close to real stress state of rock mass. (4) With the increase of the confining pressure level，the compressive strength of rock increases correspondingly. Moreover，the AE characteristics on the eve of rock fracture show sudden feature，which is represented by sudden excitation of high-energy ring rate，rapid increase of energy accumulation and sudden rock fracture without post-peak curve.
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Received: 12 January 2012
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2012, Vol. 31 
