| In underground engineering, fissure water seriously affects the mechanical properties of rock bodies, thus affecting the stability of underground engineering in water-rich areas, so it is necessary to carry out research on the mechanical properties of rock bodies under the action of fissure water pressure. In this paper, a water pressure supply device was developed to carry out uniaxial compression test of seven kinds of fissure inclination rock specimens under fissure water pressure. The results show that: under the fissure water pressure, with the increase of fissure inclination angle, the initial crack length decreases linearly, and the crack initiation point is moved from the middle of the fissure to the tip, the crack initiation stress shows a trend of decreasing and then increasing, and there is a stress minimum at 30°, and the tension destructive effect is strengthened; with the increase of the fissure water pressure, the initial crack length and the peak strength show a trend of increasing, and the time of crack initiation, the crack initiation stress, and the crack initiation angle decrease, and the tension destructive zone is increased. |