1) Non-consecutive joint
2) non-interpenetrated jointed media
3) non across jointed rock mass
4) coplanar close discontinuous joints
Rock masses containing coplanar close discontinuous joints are commonly found in nature,and their failure mechanism and strength strongly depend on the properties of joints and rock bridges,which are defined as the areas between joints.
5) joint continuity
6) through joint
The formula\'s suitability of volumetric joint count(J V) for rock mass is discussed and the study result indicates that this formula is only suit for rock mass with one through joint set or two to three perpendicularly through joint sets.