Removability

A Block is considered "Removable" if there exists at least one valid direction vector in which the block can be removed from its Joint socket. A Block which is not removable is stable, by definition.

A Block's removability is determined by the orientation and half spaces of the Joints which form it. Since a block cannot physically penetrate into the surrounding rock mass, the only valid way to remove a block is in the direction of the free surface, either sliding along the Joint(s) or by falling or lifting out of the socket. A Block with Joints which taper out toward the free surface is removable, while a Block with joints which taper in toward the free surface is not removable.

See the Theory Manual for details on how Removability of a Block is computed.