GENERATING A 3-D BLOCK PATTERN: A KEY TO BLOCKY SYSTEM STUDY. PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON NUMERICAL METHODS IN GEOMECHANICS, 11-15 APRIL 1988, INNSBRUCK, AUSTRIA. VOLUMES 1 - 3

Several methods have been developed for studying the mechanical behaviour of heavily jointed rock masses. Among those methods, the simplest ones deal with single block stability analysis, whereas the most sophisticated ones provide a means for studying large block systems. In both cases an initial block pattern is needed and is an important parameter. This article describes the development of a computer program for rebuilding three-dimensional (3D) blocky systems. To do this, a probabilistic approach has been used so as to make the most of the often sparse available data. The paper describes both the general design and the main concepts of the block generator command. This command generates a block database intended to serve as input in several other codes. One of these codes is illustrated. It enables a numerical 3D block pattern to be created and statistical information to be displayed on it. A case study is also presented as an example of the use of the model. This predicts the blocky system in the roof of a coal mine with a view to assessing the rock stability. (TRRL)