Shotcrete Gives Stronger Support At Lower Cost

During the past two years, Hecla Mining Co. has used shotcrete for ground support purposes with substantial cost savings. Hecla's experience indicates that shotcrete is an extremely effective ground support material which can be successfully employed in problem areas where various conventional systems would fail. To date, Hecla's use of shotcrete has been limited to openings where long-term high-quality support was required, to specific areas where exceptionally difficult ground conditions were encountered [ ] and, occasionally, to stope support. It is anticipated that when the necessary engineering and procurement of the components of an efficient materials handling system have been accomplished, shotcrete will be used on a routine basis in stoping and development situations. The real future of shotcrete is based, however, on the fact that this form of support offers greater opportunity for mechanization than rock bolt, timber or steel. Unlike all other support operations, which are cyclic, shotcrete is a continuous process, and therein lies its potential for incorporation into an efficient rapid excavation system. Hecla has obtained and operated both wet- and dry-process shotcrete application equipment. The operational characteristics of the two processes are presented and discussed below.