Abstract: A quick setting cementitious composition with good early strength characteristics contains, by volume, 1-30% of a cement mixture including Portland Cement, calcium aluminate and calcium sulphate, 0.001-5% of clay and water in excess of 65%. The composition is especially suited for filling cavities in underground mines, for the construction of roadside packs, and the various components of the composition can be separately pumped or otherwise conveyed to the cavity.

Abstract: An agent for accelerating hardening of cement for use in an underground mining installation employing concrete-like packs including run-of-mine coal. The agent comprises by weight one and a half parts triethanolamine, five parts sodium carbonate and one part potassium carbonate. Too rapid setting of quick setting cement is avoided by the agent because a slurry of cement in water is mixed with a slurry of agent and run-of-mine coal in bentonite in a mixer immediately before being added to a pack so that setting cement does not occur in pipes leading to the mixer.