Abstract：The cut is major factor to affect tunnel blast. The movement process of rock pieces in cut cavity is a theory base for cut blast mechanism and the parameter design. Rocks are non-transparency and brittle. It is difficult to simulate the movement of rock pieces in cut cavity by math and physics. X-ray is of strong penetration ability. It is possible to use high-speed X-ray photograph to survey insitaneous change process in rock body. The mechanism of parallel cut blast with empty holes is studied with model testing and high-speed X-ray photograph. The movement situation of rock pieces in cut cavity is gained. At the same time the study develops a new way to survey the insitaneous change process in rock body and the other non-transparency brittle medium.
