Abstract: A storable magnesium oxide/phosphate based cement having a delayed set time is provided by heating iron-containing magnesium oxide particles at an elevated temperature to provide magnesium ferrate in a gradient that increases to a maximum at the external particle surface.

Abstract: Rapid-setting compositions based on MgO and Al(H.sub.2 PO.sub.4).sub.3 and having at least a ten-minute working time, and thus suitable for mortars and road patching, form concrete-like products having increased compressive strength when fly ash is present. Fly ash reacts with aluminum phosphate to form a cementitous composition whose compressive strength is the cause of the strength increase observed in the MgO/Al(H.sub.2 PO.sub.4).sub.3 reaction product.

Abstract: A storable cement product is a dry mixture of magnesium oxide (MgO) and aluminum phosphate, or a product containing MgO and, separated therefrom, an aqueous aluminum phosphate solution, some or all of an inert aggregate component optionally being present in either product. In 45-kg samples, the mortar formed when the MgO, phosphate, water, and aggregate are combined attains an exotherm in the range of about 40.degree.-90.degree. C. after an interval of 10 minutes. The mortar hardens quickly thereafter, and is uniquely suited for patching roads under varying conditions of application and use. The reaction exotherm is controlled by a unique combination of the concentrations of the four critical components, and the surface area and particle size of the MgO.

Abstract: A grouting system for anchoring a reinforcing member in a hole at a pull strength level of at least about 175 kg/cm anchoring length within a hour, and usually within 5-10 minutes, includes a hardenable inorganic grouting composition containing an acidic oxy phosphorus compound, e.g., H.sub.3 PO.sub.4 or Al(H.sub.2 PO.sub.4).sub.3 ; a basic Group II or III metal compound capable of reacting with the oxy phosphorus compound in the presence of water to form a monolithic solid, e.g., magnesium oxide; water; and aggregate, e.g., sand. The basic compound preferably is combined with a liquid, e.g., a hydrocarbon, which is substantially nonreactive therewith to form a slush, and the slush is kept separate from an aqueous solution or mixture of the oxy phosphorus compound until use.

Abstract: In an inorganic cement grouting system for use in anchoring a reinforcing member such as a rock bolt in a hole, e.g., in a mine roof, by the reaction of the mixed components of the system so as to form a hardened grout around the reinforcing member, the two separate components of the system 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 sand is present in the cement slush and/or the reactive liquid. The sand is graded to the extent that the deviation from the median particle size is more than about .+-. 20, and usually more than about .+-. 30, percent; and particles larger than about 600 microns constitute no more than about 10 percent, and preferably about 5 percent or less, of the total volume of the sand.

Abstract: In an inorganic cement grouting system for use in anchoring a reinforcing member such as a rock bolt in a hole, e.g., in a mine roof, by the reaction of the mixed components of the system so as to form a hardened grout around the reinforcing member, which system has the following separate components: (1) a slush or sludgy mass of a particulate inorganic cement that sets by hydration and a liquid which is nonreactive therewith, preferably a hydrocarbon, and (2) water containing a particulate aggregate such as sand, a small amount of polyethylene oxide and/or polyacrylamide in the aggregate-containing water component not only thickens the water to prevent its loss from the hole, but acts as a lubricant to facilitate insertion of the reinforcing member while permitting the resulting grout to develop an acceptable shear strength.

Abstract: In an inorganic cement grouting system for use in anchoring a reinforcing member such as a rock bolt in a hole, e.g., in a mine roof, by the reaction of the mixed components of the system so as to form a hardened grout around the reinforcing member, which system has the following separate components: (1) a slush or sludgy mass of a particulate inorganic cement that sets by hydration and a liquid which is nonreactive therewith, preferably a hydrocarbon, and (2) water, higher early strength is achieved when the cement is one which contains (by weight) about from 20 to 40 percent of 3CaO.3Al.sub.2 O.sub.3.CaSO.sub.4 and about from 10 to 35 percent of chemically unbound CaSO.sub.4, the remainder being substantially .beta.-2CaO.SiO.sub.2. The strength advantage obtained with this cement when used in nonaqueous slush form makes it particularly adapted for use in a system for anchoring rock bolts in a mine roof.