There are two main reasons for this error:
1. Target number of zones cannot be achieved
StopeX attempts to generate a number of zones within ±600,000 of the target number of zones. If after several iterations StopeX is unable to meet this target, the user will be prompted to enter a new recommended target number of zones. If the user enters 0, FLAC3D will return an ‘Index 1 out of range (1,0)’ error. Alternatively, the user can generate a new input file with a different target number of zones. It is recommended that neither the target number of zones or the number of generated zones should exceed 2.6 million.
2. Stress field and/or material parameters are invalid
During the initial equilibrium stage, StopeX has generated zones which are in tension. This likely means the stress field and/or material parameters are invalid. In StopeX, ensure the ground surface elevation, stress gradient and stress orientations have been entered correctly. Using CAD software, also ensure that input geometries are at the correct elevation.
