Abstract:Temperature is one of the important factors affecting the mechanical properties of rocks. To investigate the influences of temperature on fracture characteristics and strength of marble

the uniaxial and triaxial compression tests on marble samples with natural state and heated with 200℃ or 800℃ have been carried out. The results show that thermal treatments have great influences on the failure forms and strength of marble samples. Under the condition of uniaxial compression，the natural specimen failed in tension-shear mode

on the contrast

the specimens heated by high temperature tend to fail in tension. In triaxial compression tests

the natural specimens failed in shear mode. The samples heated with 200℃ failed in modes of shear and the tension-shear. The specimens heated with 800℃ failed in mode of shear

tension-shear and bulging deformation. After heated with 200℃

the specimens have a slight increase in cohesion

and little variations in internal friction angle. But After heated with 800℃

the specimens have a considerable reduction in cohesion

and a slight increase in internal friction angle. Rock failure modes become complex and strengths disperse widely because of heating. It is more reasonable for Mogi-Coulomb failure criterion to analysis strengths of the marble specimens under natural or heated condition.