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AssigneeE. I. Du Pont de Nemours and Company
InventorDavid L. Coursen
Estimating the term…
In a method of anchoring a reinforcing member such as a rock bolt in a hole, e.g., in a mine roof,wherein two separate components of an inorganic cement grouting system are mixed, preferably in the hole, e.g., by the rotation of the reinforcing member, whereby the components react to form a hardened grout around the reinforcing member, the two components of the system delivered into the hole are: (1) a slush or sludgy mass of a particulate inorganic cement, e.g., an hydraulic cement, and a liquid which is nonreactive therewith, preferably a hydrocarbon, and (2) a liquid, e.g., water, which is reactive with the cement; and a particulate aggregate such as sand preferably is present in the cement slush and/or the reactive liquid. The inorganic cement constitutes more than 10 percent, and the weight of any aggregate present is no more than about 80 percent, of the total weight of the two components. The two components preferably are delivered into the hole separately, e.g., from separate feeding conduits or, more preferably, in separate compartments of a frangible package, which is broken by the penetration and rotation of the reinforcing member. The cement composition in slush form and controlled aggregate content impart lubricity to the system for easy insertion and rotation of a reinforcing member, and make the cement component and the combined components pumpable through small-diameter passageways, while permitting the development of an adequate pull strength in the hardened grout formed around the reinforcing member when the mixed components react.
A method of anchoring a reinforcing member in a hole in rock strata comprising
In a grouting system for use in a hole in rock strata in combination with a reinforcing member wherein a hardened grout is formed around the reinforcing member in the hole by the reaction of at least two mixed components of a hardenable inorganic grouting composition, thereby anchoring the reinforcing member in the hole, said components being adapted to be forced into an annulus formed between said reinforcing member and the wall of said hole by the introduction of said reinforcing member into said components before any substantial hardening of said composition has occurred, the improvement comprising an inorganic grouting composition comprising controlled amounts of at least two components, the first of said components (a) comprising a slush comprising a particulate inorganic cement and a liquid which is nonreactive therewith, and the second of said components (b), separated from the first, comprising a liquid which is reactive with said inorganic cement, said inorganic cement constituting more than 10 percent by weight of the total weight of components (a) and (b), and said components (a) and (b) being (1) present in the hole, or outside the hole and adapted to be delivered thereto separately or in freshly combined condition;
Dependencies are inferred from the claim text.