A laboratory study of backfilling bord and pillar voids using fly ash slurry

摘要

In various locations worldwide, fly ash slurry has been injected into underground bord and pillar coal mine workings to provide support, and the method was recently used successfully for the Ipswich Motorway upgrade in southeast Queensland, Australia. This paper describes laboratory testing, and the results obtained, aimed at achieving an improved understanding of the backfilling processes and to provide guidance for the effective application of fly ash slurry injection to stabilise bord and pillar underground coal workings and allow the safe development of the surface.