A low-density, high-strength concrete composition that is lightweight and self-compacting or non-self-compacting, with a low weight-fraction of aggregate to total dry raw materials, and a highly-homogenous distribution of a non-absorptive and closed-cell lightweight aggregate such as glass microspheres or copolymer polymer beads or a combination thereof, and the steps of providing the composition or components. Lightweight concretes formed therefrom have low density, high strength-to-weight ratios, and high R-value. The concrete has strength similar to that ordinarily found in structural lightweight concrete but at a lower density, such as an oven-dried density as low as 40 lbs./cu.ft. Such strength-to-density ratios range approximately from above 30 cu.ft/sq.in. to above 110 cu.ft/sq.in., with a 28-day compressive strength ranging from about 3400 to 8000 psi.

A low-density, high-strength concrete composition that is lightweight and self-compacting or non-self-compacting, with a low weight-fraction of aggregate to total dry raw materials, and a highly-homogenous distribution of a non-absorptive and closed-cell lightweight aggregate such as glass microspheres or copolymer polymer beads or a combination thereof, and the steps of providing the composition or components. Lightweight concretes formed therefrom have low density, high strength-to-weight ratios, and high R-value. The concrete has strength similar to that ordinarily found in structural lightweight concrete but at a lower density, such as an oven-dried density as low as 40 lbs./cu.ft. Such strength-to-density ratios range approximately from above 30 cu.ft/sq.in. to above 110 cu.ft/sq.in., with a 28-day compressive strength ranging from about 3400 to 8000 psi.

The invention concerns a method for producing gypsum boards, wherein a liquefier for the gypsum slurry is foamed with gas to provide a foam having a water content of less than 85 wt.-%, then incorporated into a gypsum/water mixture and the mixture thus obtained is applied on a two dimensional substrate. The incorporation of the liquefier in foamed form allows for a significant reduction of the amount of liquefier required to provide a desired flowability of the gypsum/water mixture, thus allowing the production of gypsum boards with similar characteristics with less liquefier. The invention further concerns gypsum board prepared using this process, apparatuses for producing gypsum boards using this process and the use of a corresponding liquefier foam to minimize the amount of liquefier required to establish a desired flowability of a gypsum/water mixture.

The invention concerns a method for producing gypsum boards, wherein a liquefier for the gypsum slurry is foamed with gas to provide a foam having a water content of less than 85 wt.-%, then incorporated into a gypsum/water mixture and the mixture thus obtained is applied on a two dimensional substrate. The incorporation of the liquefier in foamed form allows for a significant reduction of the amount of liquefier required to provide a desired flowability of the gypsum/water mixture, thus allowing the production of gypsum boards with similar characteristics with less liquefier. The invention further concerns gypsum board prepared using this process, apparatuses for producing gypsum boards using this process and the use of a corresponding liquefier foam to minimize the amount of liquefier required to establish a desired flowability of a gypsum/water mixture.

A use of a thiosulfate as a retarder for a cement paste comprising a magnesium phosphate cement.

A use of a thiosulfate as a retarder for a cement paste comprising a magnesium phosphate cement.

A joint compound system includes a set-inhibited, pre-wetted, setting-type, ready-mix joint compound and a set initiator. The set-inhibited, pre-wetted, setting-type joint compound includes a ready-mixed, setting-type joint compound base with a calcium-free phosphate set preventing agent that impedes chemical hydration of a gypsum component of the setting-type joint compound. The joint compound base is free of calcium carbonate. The set initiator includes alum to reinitiate the chemical hydration reactions.

A joint compound system includes a set-inhibited, pre-wetted, setting-type, ready-mix joint compound and a set initiator. The set-inhibited, pre-wetted, setting-type joint compound includes a ready-mixed, setting-type joint compound base with a calcium-free phosphate set preventing agent that impedes chemical hydration of a gypsum component of the setting-type joint compound. The joint compound base is free of calcium carbonate. The set initiator includes alum to reinitiate the chemical hydration reactions.

A method for preventing formation of rust-colored stains on the surface of a hydraulic composition includes mixing the hydraulic composition with an additive for hydraulic binder including at least a dialkanolamine including from 2 to 8 carbon atoms, and at least a polyol preferably chosen from a diol, a triol, a tetraol and mixtures thereof. Other uses include a grinding aid for hydraulic binder precursor, and/or improving the compressive strength of a set hydraulic composition.

A method for preventing formation of rust-colored stains on the surface of a hydraulic composition includes mixing the hydraulic composition with an additive for hydraulic binder including at least a dialkanolamine including from 2 to 8 carbon atoms, and at least a polyol preferably chosen from a diol, a triol, a tetraol and mixtures thereof. Other uses include a grinding aid for hydraulic binder precursor, and/or improving the compressive strength of a set hydraulic composition.