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Abstract The uniaxial compression tests on marbles were performed under six levels of strain rates ranging from 2×10－5 to 5×10－3 s－1 by using RMT–150B servo machine. The effects of strain rate on stress rate，peak strength，elasticity modulus，Poisson?s ratio，softening modulus，strain at peak stress，storage energy，releasing energy，and fracture behavior were analyzed. The results show that the uniaxial compression process including four stages：compression，elasticity，yielding and failure stages under different strain rates. The relationship of stress rate and logarithm of strain rate could be expressed in exponential form. The peak strength of marble had a positive correlation with strain rate which could be expressed in quadratic polynomial form. The strain rate has little influence on elasticity modulus，softening modulus，and peak strain. The Poisson?s ratio has a negative correlation with strain rate，which could be expressed in exponential form. The accumulated energy prior to stress peak and released energy after stress peak has a positive correlation with strain rate；and the higher the strain rate is，the more serious cracking is. When strain rate is less than 5 × 10－4 s－1，the samples mainly present shear failure mode. The failure mode would be changed from local shear failure to overall shear failure with the increase of strain rate；and it is easier to form a cone-shape failure under high strain rate. The investigation results can provide a certain references for rockburst prevention and engineering seismic design.
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Received: 19 November 2012
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2013, Vol. 32 
