ABSTRACT
This paper describes a methodology for the choice of rockbolt support systems, which is based on the “convergence – confinement” and “critical depths” concepts introduced by Hoek & Brown and Sauku respectively. The methodology has been coded in the PREGAL computer program, which permits the user to study different rockbolt types and patterns for a given underground support situation in a timely manner and then choose the most appropriate ones. To demonstrate the methodology and the operation of PREGAL, a case study is presented, which estimates the optimum rockbolt pattern in a section of the Klos-Bulqiza headings in the underground chromite mine of Bulqiza, Albania.
