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Abstract By uniaxial tests on salt rock specimens under different temperatures，it is shown that the uniaxial compressive strength of salt rock drops significantly and the peak strain increases gradually with the increase of temperature. Through the cyclic loading test under different temperatures，in which the upper and lower limit stresses are chosen according to the uniaxial compressive strength under different temperatures，it is found that：(1) The fatigue life of salt rock under the same stress ratio becomes longer as the temperature rises. (2) The fatigue damage development mode of salt rock under different temperatures all includes three stages：slow damage stage，uniform damage stage and accelerated damage stage. (3) The proportion of uniform damage stage increases as the temperature becomes higher. (4) The curve of volumetric strain shows the three stages more obviously than the axial strain curve. Finally，the fatigue damage of salt rock is analyzed by using the analytical formulas for elastoplastic material damage. It is indicated that the development mode of salt rock fatigue damage is matched with that of the volumetric strain. Therefore，the volumetric strain is more appropriate for describing the fatigue damage of salt rock.
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Received: 27 April 2012
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2012, Vol. 31 
