Association analysis of pore development characteristics and uniaxial compressive strength property of granite under freezing-thawing cycles

For understanding the relationship between microstructure characteristics and mechanical property of granite,nuclear magnetic resonance( NMR) measurement and rock mechanical test were conducted in this study. The relationship between NMR porosity,NMR T2 spectrum area and uniaxial compressive strength were analyzed respectively.The results show that the pore development has important influence on rock damage. There are exponential distribution between NMR porosity,NMR T2 spectrum area and uniaxial compressive strength. The pore distribution of rock has important effect on rock mechanical property and macro damage characteristics. The pore development characteristics of rock samples under freezing and thawing cycles were studied by using fractal theory and the fractal dimension values were obtained. The results indicate that the pore evolvement under freezing and thawing cycles was self-similar. The bigger the fractal dimension value,the more pore develops,and the smaller the uniaxial compressive strength.