Research of stowing material for filling of free underground spaces of old mine works

Abstract

In the areas with long-lasting coal mining (many centuries ago) a number of old mining works have emerged as a communication channel for uncontrolled methane outputs. Disposal of these underground areas represents not only a technical but also an economically challenging task, which requires a combination of technical knowledge from the use of materials and the creation of free spaces with an emphasis on high environmental protection. Semi fluid mixtures based on fly ash and cement binder and waste sand bits appear to be the ideal solution for filling these open spaces in terms of their behavior and production economics. These building filler compounds are able to prevent the transport of mining gases at individual discontinuous sites of the mining environment. Their final strengths will ensure the stability of the sanitized site and at the same time will prevent the further creation of communication spaces of the surrounding rock environment.