Mineral fines reduce OPC content in concrete, mortar and other cementitious compositions, typically in combination with a pozzolanically active SCM. Mineral fines can replace and/or augment a portion of hydraulic cement and/or fine aggregate. Mineral fines can replace a portion of cement binder and fine aggregate as an intermediate that fills a size void between largest cement particles and smallest fine aggregate particles. Supplemental lime can enhance balance of calcium ions in the mix water and/or pore solution. Supplemental sulfate can address sulfate deficiencies caused by high clinker reduction, use of water reducers and/or superplasticizers, and SCMs containing aluminates. Concentrated or pure carbon dioxide (CO.sub.2) can be used to passivate alkaline values in highly alkaline materials, such as concrete washout fines, CKD, class C flyash, incinerator ash, bottom ash, or biomass ash. CO.sub.2 passivation or sequestration can be carried out before, during or after forming an initial concrete mix.

A method for continuously forming gypsum-based panels of high fixing strength comprises the steps of: •forming a mixture comprising stucco, non-pregelatinized migratory starch, glass fibre, fluidizer and water; •casting the mixture in a continuous band; •maintaining the band under conditions sufficient for the stucco to form an interlocking matrix of set gypsum; •cutting the band to form one or more wet panel precursors; and •drying the wet panel precursor to form one or more gypsum-based panels. •The weight ratio of water to stucco in the mixture is less than 0.7; •the stucco is present in the mixture in an amount of over 60 wt % relative to the total solids content of the mixture; •the starch is present in the mixture in an amount of over 3 wt % relative to the stucco; •the glass fibre is present in the mixture in an amount of over 1 wt % relative to the stucco; •the fluidizer is present in the mixture in an amount of at least 0.1 wt % relative to the stucco; and the density of the gypsum-based panel is greater than 700 kg/m.

A method for continuously forming gypsum-based panels of high fixing strength comprises the steps of: •forming a mixture comprising stucco, non-pregelatinized migratory starch, glass fibre, fluidizer and water; •casting the mixture in a continuous band; •maintaining the band under conditions sufficient for the stucco to form an interlocking matrix of set gypsum; •cutting the band to form one or more wet panel precursors; and •drying the wet panel precursor to form one or more gypsum-based panels. •The weight ratio of water to stucco in the mixture is less than 0.7; •the stucco is present in the mixture in an amount of over 60 wt % relative to the total solids content of the mixture; •the starch is present in the mixture in an amount of over 3 wt % relative to the stucco; •the glass fibre is present in the mixture in an amount of over 1 wt % relative to the stucco; •the fluidizer is present in the mixture in an amount of at least 0.1 wt % relative to the stucco; and the density of the gypsum-based panel is greater than 700 kg/m.

A reduced weight, reduced density gypsum panel that includes high expansion vermiculite with fire resistance capabilities that are at least comparable to (if not better than) commercial fire rated gypsum panels with a much greater gypsum content, weight and density.

A reduced weight, reduced density gypsum panel that includes high expansion vermiculite with fire resistance capabilities that are at least comparable to (if not better than) commercial fire rated gypsum panels with a much greater gypsum content, weight and density.

Gypsum board having improved performance is obtained by controlling the distribution of starch in the gypsum core of the board and the gelling temperature of the starch. Starch migration in the board is controlled by the degree of acid-modification, to adjust the starch viscosity profile. The starch gelling temperature is controlled by chemical modification of the starch —OH groups.

The use of polyol having a functionality of 4 or less and an OH group density of at least 0.033 mol OH per g polyol as a composition for reducing shrinking of construction chemicals on the basis of a hydraulic binder comprising a) alumina cement and/or calcium sulfoaluminate cement, b) calcium sulfate, and c) optionally Portland cement.

The use of polyol having a functionality of 4 or less and an OH group density of at least 0.033 mol OH per g polyol as a composition for reducing shrinking of construction chemicals on the basis of a hydraulic binder comprising a) alumina cement and/or calcium sulfoaluminate cement, b) calcium sulfate, and c) optionally Portland cement.

The invention concerns construction materials based on a mineral binder, which includes a synergistically effective hydrophobisation mixture. The invention also relates to methods for processing of such construction materials and the use of a synergistically effective mixture for the hydrophobisation of a mineral binder based construction material.

The invention concerns construction materials based on a mineral binder, which includes a synergistically effective hydrophobisation mixture. The invention also relates to methods for processing of such construction materials and the use of a synergistically effective mixture for the hydrophobisation of a mineral binder based construction material.