ROCK3D is a program for stability analysis of removable blocks on planar rock slopes. It identifies and analyses all the blocks that have formed under each kinematic mode. Once the geometry of the rock blocks has been identified, the bolt forces necessary to reach a required safety factor are calculated.

The structural geology data collection is carried out through the introduction of the joint orientations and the co-ordinates of the end points of the joint traces that are visible on the slope surface.

The rock slope orientation and the rock mass parameters are also necessary for the evaluation of the safety factors and for the design of the rock bolts.

The analysis of the discontinuities is performed through hierarchical and non-hierarchical clustering procedures, that allow one to identify the joint sets.

The kinematic modes that could give rise to the formation of removable blocks are determined using the Goodman and Shi "Key Block Theory".

The program calculates the maximum closed contours that result from the intersection of the joint traces, which follow a given kinematic mode. The procedure should be repeated for each kinematic mode to identify the worst safety conditions.

The program then calculates the shape of the complex blocks that can be obtained as a union of all the elementary polyhedra that are compatible with the selected kinematic mode, and which are contained within the closed contours identified in the previous stage.
The volume and surfaces of each block are then calculated.

The computation ends with the determination of the rock block safety factors and of the rock bolt forces that are necessary to obtain the required stability conditions.

As an option, the program can generate a random distribution of the joints on the rock slope face, to formulate hypotheses on the behaviour of the slope after a subsequent stage of excavation.

The output is made up of the projection on equal-angle stereonets of the joint sets, the plot of the joint traces on the slope face, the polar stereographic projection used in the "Key Block Theory" and the perspective projection of the rock blocks.

It is also possible to produce a left and a right view of the blocks, which can be seen in three dimensions with a common stereoscope.

Listings that include the input data and the results of the various calculations can also be generated.

EXAMPLES OF GRAPHIC OUTPUTS

Here are some examples of program-generated graphic outputs:

• An example of the result of cluster analysis;
• The Goodman and Shi polar projection;
• A map of the traces and contours of the maximum removable blocks for joint pyramid 1111;
• The maximum removable blocks produced by joint pyramid 1111;
• A map of the traces and contours of the maximum removable blocks for joint pyramid 1110;
• The maximum removable blocks produced by joint pyramid 1110;
• A map of traces and contours of the maximum removable blocks for joint pyramid 1101;
• The maximum removable blocks produced by joint pyramid 1101.