Abstract With newly-built experimental equipment,tests on 100 mm×100 mm×100 mm granite specimens under vertical static stresses with lateral disturbance have been conducted. Numerical simulation with software PFC3D was used to reveal the inner mechanism of failure. The acoustic emission(AE) system PCI–2 was used to pick up AE signals. It?s found that the peak AE energy event usually happened at the unloading stage of the disturbance stress. The peak AE energy event tended to happen earlier and more frequently with the increase of the static stresses. Wave velocities at different positions were used to evaluate the damage distribution of the specimen at different loading conditions. RA values were also used to investigate the failure mechanism of specimens. When the static stress was low,only few shear cracks were triggered and a small shear failure zone was observed at the direct contact zone of the disturbance load. When the static stress was high,the shear cracks and the tensile cracks were both activated and the proliferation of tensile cracks resulted in the structural failure of specimens eventually. Numerical investigation also demonstrated this phenomenon.
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Received: 31 October 2013
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