FROZEN BACKFILL MIX FORMULATIONS AND PROCESS FOR USE THEREOF IN UNDERGROUND MINING APPLICATIONS

摘要

Formulations are provided for producing structural members or back fill formine stopes in environments havingsub zero temperatures such as permafrost. The formulations having constituentsincluding crushed rock (rockfill) powdered tail-ings,ice and water in specific ratios with attention to the prescribed gradationsof the rockfill and tailings. The tailings, a readilyavailable and very finely divided material, fill the naturally existing voidsin the rockfill. The gradation of the rockfill and the bulkdensity of the rockfill establish the rockfill/tailings ratio, which has beendetermined to lie between 1 and 3 or from 50/50 to about75/25 for optimum strength. The ice in the mix design arises from the pre-existing moisture content in the rock and tailings, typi-cally2% to 5% of the rockfill and 8% to 25% for the tailings. The change of stateof liquid after to ice on the particle surfaces isthe binding mechanism of the system and is enhanced by vigorous mixing.