Mixed volume of aluminous cement affected to grouting materialperformances of borehole sealing for gas drainage

According to a low fluidity and long setting time of the cement base grouting material, no active support force applied to the borehole wall, no clear interactive relationship between the material performances and other problems, with the experiment to change the mixed volume of the aluminous cement, the paper had a study on the mixed volume of the aluminous cement affected to the material fluidity, setting time, swelling rate and compressive strength and an analysis on the function of the aluminous cement in the material curing mechanism and the swelling mechanism. An interactive relationship between the material swelling volume and the compressive strength was studied. With the industrial tests conducted on the three group materials of the experiment mixing optimized selections, the grouting material suitable for the sealing of the gas drainage borehole was obtained. The results showed that with the material hydration reaction of the aluminous cement, the material fluidity and material setting time would be reduced. With the grout alkaline environment changed of the aluminous cement and the production of hydration product, the material swelling volume could be controlled and the material strength could be improved. The swelling source of the material were mainly from the gas phase swelling, the ettringite swelling and the hydration swelling of the calcium oxide and magnesium oxide. The gas retention capacity of the material would be the relation belt between the swelling volume and compressive strength of the material.