Abstract: Considering the problems related to rock blasting under deep high in-situ stress， we conducted crater blasting tests on sandstone specimens under different unidirectional compressive stresses. The influence of static stress on the formation and propagation of crack network in the process of crater blasting was analyzed. The concept of failure zones formed in blasting crater， namely， block failure zone， transition zone and flaky spalling zone was put forward. The influence of static stress on the three failure zones in blasting crater and the characteristics of rock blasting failure under different static stress conditions were elucidated.The results show that static stress promotes the formation of cracks parallel to its own direction and inhibits the formation of cracks perpendicular to its own direction， thus changing the shape of the crack network. The static stress promotes the formation of blasting crater failure zone parallel to its own direction， and has the greatest influence on flaky spalling zone， followed by block failure zone and transition zone， and has little effect on the failure zone perpendicular to its own direction.When stress-strength ratio reaches 0.15， the influence of static stress on blasting effect needs to be considered.

Key words: high stress; electrical explosion; crater blasting; crack network; distinction of failure zone