Abstract:Based on the hydraulic servo testing machine and the split Hopkinson pressure bar (SHPB) with a diameter of 100 mm, the dynamic / static experiment compression tests of red-sandstone with different saturated degree of water are tested, the mechanical properties of the rock is studied, and the experimental conclusion from the perspective is analyzed. The conclusion is that there is a critical saturated degree Sl for the impact on rock strength. when the saturated degree is less than Sl , the intensity linearly decreases with the increase of saturated degree. when the saturated degree is larger than Sl, the change range of rock strength is very small along with the rising of the satisfied degree. The minimal peak strain appears at the saturated degree of 0.42 and the peak strain under the condition of dynamic test is more sensitive to the saturated degree. The Peak modulus linearly decreases with the increase of saturated degree. From a judgment upon the influence of the saturated degree on the peak modulus from the Microcosmic view, three key parameters should be seized, i.e. loading ability of mineral grains and cement between them, coordinate ability to deformation of them and degree of pore development. Along with the rising of the saturated degree of water, the strain rate effect of rock mechanics properties have become more and more obvious. Among them, the saturated degree of water has the greatest influence on the strain rate effect of rock strength and the smallest effect on the strain rate effect of rock modulus.