Abstract: A hydraulic binder based on a sulfoaluminate clinker including the mineralogical phases ye'elimite C4A3$, mayenite C12A7, free lime CaO, and optionally belite C2S, characterized in that, in the clinker, the mineralogical phases are 20% to 50% by weight of ye'elimite C4A3$ phase, 5% to 80% by weight of mayenite C12A7 phase, and 1% to 5% by weight of free lime CaO, the weight ratio between the mayenite C12A7 and ye'elimite C4A3$ phases being between 0.1 and 10. The binder can be used to treat polluted soils, in particular soils with a leachable fraction greater than 0.4% that contains predominantly anions and/or heavy metal cations by mixing the soil with the hydraulic binder, in soil/binder weight proportions of between 1 and 40 parts of binder for 100 parts of soil. It makes it possible to stabilize soils which are polluted or to stabilize soils before dumping.

Abstract: A process for treating polluted soils, in particular soils with a leachable fraction greater than 0.4%, wherein the leachable fraction contains predominantly anions, in particular sulfate ions, and/or heavy metals, includes mixing the soil with a sulfoaluminate-clinker-based hydraulic binder, in soil/binder weight proportions of between 1 and 40 parts of binder per 100 parts of soil, the sulfoaluminate clinker containing more than 50% by weight of ye'elimite C4A3S phase, less than 15% by weight of belite C2S phase, and from 1% to 5% by weight of free lime CaO. The process is used for stabilizing soils in situ or before dumping, soils polluted in particular with sulfate anions and/or heavy metal cations.

Abstract: Cement material, curable in the presence of water and including a hydraulic binder composition, which contains a mixture of hydraulic binders and a mixture of sulphate sources, wherein the hydraulic binder mixture includes: at least one hydraulic binder containing an alite-type mineralogical phase and at least one hydraulic binder containing an aluminate-type mineralogical phase, mainly consisting of ye'elimite (C4A3$) or a mixture of ye'elimite and calcium monoaluminate (CA), the mixture of sulphate sources containing at least one sulphate source with a solubility of <4 g·L?1, and at least one sulphate source with a solubility >4 g·L?1, the cement material optionally including mineral additions, fine granulates, large granulates and additives. The curable cement material is useful as a material capable of setting in cold weather, in particular a concrete, a mortar, a grout, a coating or a cement paste to be used at a temperature of ?10° C. to +5° C.

Abstract: Disclosed is a structural lightweight concrete or mortar composition which, in the fresh state, includes an hydraulic binder, aggregate, and water, characterized in that the composition includes: an hydraulic binder content including cement and optional additions, which is greater than or equal to 280 kg/m3 of fresh concrete, coarse aggregate and/or fine aggregate, a volume proportion of at least 70% of the fine and/or coarse aggregate consisting of fine and/or coarse lightweight particles, the actual dry density of which is between 800 and 1,600 kg/m3, the total amount of aggregate being greater than or equal to 500 L/m3 of fresh concrete, a superplasticizer, at least one thickening agent, and effective water in an effective water/hydraulic binder weight ratio of between 0.40 and 0.65. The composition can be used for producing a self-placing lightweight concrete.

Abstract: An anti-foam additive for a cement composition, including a fatty alcohol ester that is soluble in an aqueous medium at acidic pH, and hydrolysable in a basic medium, i.e. when the ester is incorporated into the cement composition, while releasing an active anti-foam molecule. This ester is preferably a fatty alcohol ester of a quaternary ammonium carboxylate, that is soluble in an aqueous solution of a superplasticizer, such as a polycarboxylate with poly(ethylene oxide) side chains. The additive can used for reducing the amount of air entrained during mixing or blending of mortars or concretes.

Abstract: A hydraulic binder based on a sulfoaluminate clinker including the mineralogical phases ye'elimite C4A3$, mayenite C12A7, free lime CaO, and optionally belite C2S, characterized in that, in the clinker, the mineralogical phases are 20% to 50% by weight of ye'elimite C4A3$ phase, 5% to 80% by weight of mayenite C12A7 phase, and 1% to 5% by weight of free lime CaO, the weight ratio between the mayenite C12A7 and ye'elimite C4A3$ phases being between 0.1 and 10. The binder can be used to treat polluted soils, in particular soils with a leachable fraction greater than 0.4% that contains predominantly anions and/or heavy metal cations by mixing the soil with the hydraulic binder, in soil/binder weight proportions of between 1 and 40 parts of binder for 100 parts of soil. It makes it possible to stabilize soils which are polluted or to stabilize soils before dumping.

Abstract: A process for treating polluted soils, in particular soils with a leachable fraction greater than 0.4%, wherein the leachable fraction contains predominantly anions, in particular sulfate ions, and/or heavy metals, includes mixing the soil with a sulfoaluminate-clinker-based hydraulic binder, in soil/binder weight proportions of between 1 and 40 parts of binder per 100 parts of soil, the sulfoaluminate clinker containing more than 50% by weight of ye?elimite C4A3S phase, less than 15% by weight of belite C2S phase, and from 1% to 5% by weight of free lime CaO. The process is used for stabilizing soils in situ or before dumping, soils polluted in particular with sulfate anions and/or heavy metal cations.

Abstract: Disclosed is a structural lightweight concrete or mortar composition which, in the fresh state, includes an hydraulic binder, aggregate, and water, characterized in that the composition includes: an hydraulic binder content including cement and optional additions, which is greater than or equal to 280 kg/m3 of fresh concrete, coarse aggregate and/or fine aggregate, a volume proportion of at least 70% of the fine and/or coarse aggregate consisting of fine and/or coarse lightweight particles, the actual dry density of which is between 800 and 1,600 kg/m3, the total amount of aggregate being greater than or equal to 500 L/m3 of fresh concrete, a superplasticizer, at least one thickening agent, and effective water in an effective water/hydraulic binder weight ratio of between 0.40 and 0.65. The composition can be used for producing a self-placing lightweight concrete.

Abstract: A liquid aqueous suspension of polysaccharide, contains a mass concentration of at least one polysaccharide of between 15 and 35% in the form of partially hydrated particles dispersed in an aqueous solution of a strong base salt, excluding ammonium salts, with an ionic strength of between 1.25 mol/L and 15 mol/L, has a pH greater than 9 and contains at least one non-phyllitic crystalline mineral powder, referred to hereafter as filler, which is chemically inert in the aqueous suspension and which has a grain size of between 0.1 and 100 micrometers and an attapulgite in micronized form, the aqueous suspension being stable at least in a temperature range from 5 to 30° C. The suspension is suitable for use as an agent for thickening cementitious compositions.

Abstract: A water retention agent for a cementitious composition, characterized in that it takes the form of a liquid aqueous suspension of at least one polysaccharide at a mass concentration of between 15 and 30% in an aqueous solution of a strong base salt, excluding ammonium salts, with an anionic strength of between 1.25 mol/L and 15 mol/L, having a pH greater than 9 and containing an attapulgite in micronized form and at least one non-phyllitic mineral powder, referred to hereafter as filler, which is chemically inert in the aqueous suspension and which has a grain size of between 0.1 and 100 micrometers, the aqueous suspension being stable at least in a temperature range of between 5° C. and 30° C. The water retention agent is suitable for increasing both the viscosity and the water retention capacity of cementitious compositions without affecting the spreading ability thereof.

Abstract: An anti-foam additive for a cement composition, including a fatty alcohol ester that is soluble in an aqueous medium at acidic pH, and hydrolysable in a basic medium, i.e. when the ester is incorporated into the cement composition, while releasing an active anti-foam molecule. This ester is preferably a fatty alcohol ester of a quaternary ammonium carboxylate, that is soluble in an aqueous solution of a superplasticizer, such as a polycarboxylate with poly(ethylene oxide) side chains. The additive can used for reducing the amount of air entrained during mixing or blending of mortars or concretes.

Abstract: A water retention agent for a cementitious composition, characterized in that it takes the form of a liquid aqueous suspension of at least one polysaccharide at a mass concentration of between 15 and 30% in an aqueous solution of a strong base salt, excluding ammonium salts, with an anionic strength of between 1.25 mol/L and 15 mol/L, having a pH greater than 9 and containing an attapulgite in micronized form and at least one non-phyllitic mineral powder, referred to hereafter as filler, which is chemically inert in the aqueous suspension and which has a grain size of between 0.1 and 100 micrometres, the aqueous suspension being stable at least in a temperature range of between 5° C. and 30° C. The water retention agent is suitable for increasing both the viscosity and the water retention capacity of cementitious compositions without affecting the spreading ability thereof.

Abstract: A liquid aqueous suspension of polysaccharide, contains a mass concentration of at least one polysaccharide of between 15 and 35% in the form of partially hydrated particles dispersed in an aqueous solution of a strong base salt, excluding ammonium salts, with an ionic strength of between 1.25 mol/L and 15 mol/L, has a pH greater than 9 and contains at least one non-phyllitic crystalline mineral powder, referred to hereafter as filler, which is chemically inert in the aqueous suspension and which has a grain size of between 0.1 and 100 micrometres and an attapulgite in micronized form, the aqueous suspension being stable at least in a temperature range from 5 to 30 30° C. The suspension is suitable for use as an agent for thickening cementitious compositions.

Abstract: The self-leveling fluid screed cement composition with limited shrinkage, formed by a mixture of a cement binder, a fluidizing adjuvant, granulates and water, is characterized in that the binder includes 70% to 85% by weight of Portland cement, 7% to 18% by weight of sulfo-aluminous clinker, and 6% to 14% by weight of calcium sulfate, with a calcium sulfate C$/calcium sulfo-aluminate C4A3$ molar ratio of between 5 and 7 and a water/binder ratio by weight of between 0.60 and 0.90. The self-leveling fluid screed that is thus produced has a mechanical resistance to its compression at 24 hours that is at least equal to 1 MPa, shrinkage at 7 days, measured under a relative hygrometry of 50%, less than 500 ?m/m, and an endogenic expansion value that is measured at 7 days, less than 1,000 ?m/m, as well as a very slight lifting of edges.

Abstract: A method of treating marine or river dredging sediments, especially harbour zone sediments, whose free water content is between 40% and 80% by weight, for the purpose of obtaining a solid material which is easy to handle, includes the following successive steps: mixing the sediments with a treatment composition including a sulphoaluminate binder and at least one other component selected from a sulphate source and a catalyst of the hydration reactions of the sulphoaluminate binder; a step of setting of the mixture, leading to a compact mixture having a free water content of less than 20% by weight; then fractionating the compact mixture. The sediment thus treated may be incorporated into concrete or mortar formulas, which then have leachable fractions of less than 1% by weight.

Abstract: The self-leveling fluid screed cement composition with limited shrinkage, formed by a mixture of a cement binder, a fluidizing adjuvant, granulates and water, is characterized in that the binder includes 70% to 85% by weight of Portland cement, 7% to 18% by weight of sulfo-aluminous clinker, and 6% to 14% by weight of calcium sulfate, with a calcium sulfate C$/calcium sulfo-aluminate C4A3$ molar ratio of between 5 and 7 and a water/binder ratio by weight of between 0.60 and 0.90. The self-leveling fluid screed that is thus produced has a mechanical resistance to its compression at 24 hours that is at least equal to 1 MPa, shrinkage at 7 days, measured under a relative hygrometry of 50%, less than 500 ?m/m, and an endogenic expansion value that is measured at 7 days, less than 1,000 ?m/m, as well as a very slight lifting of edges.

Abstract: A method of treating marine or river dredging sediments, especially harbour zone sediments, whose free water content is between 40% and 80% by weight, for the purpose of obtaining a solid material which is easy to handle, includes the following successive steps: mixing the sediments with a treatment composition including a sulphoaluminate binder and at least one other component selected from a sulphate source and a catalyst of the hydration reactions of the sulphoaluminate binder; a step of setting of the mixture, leading to a compact mixture having a free water content of less than 20% by weight; then fractionating the compact mixture. The sediment thus treated may be incorporated into concrete or mortar formulas, which then have leachable fractions of less than 1% by weight.

Abstract: A cement composition for a self-levelling concrete, includes a mixture of rheology-modifying additives, the combination of at least a first agent for substantially increasing the shear threshold of the concrete in the fluid state, selected from a natural polysaccharide ether, a hydroxyalkyl guar ether, a hydroxyethylcellulose or a hydroxypropyl guar, which are hydrophobically modified with the introduction of hydrophobic side grafts, and at least a second viscosity-increasing agent for substantially increasing the viscosity of the concrete in the fluid state, selected from a non-hydrophobically-modified hydroxyalkylcellulose having a degree of polymerization between approximately 500 and approximately 4500 and a viscosity of less than 50 PA·s in aqueous solution at 2 wt.-% and a poly (ethylene oxide), in order to limit or prevent the dynamic segregation of granulates in the concrete during the implementation thereof.

Abstract: The photocatalytic granular mixture for mortar and concrete includes a photocatalyst in the form of at least two granular classes with different B.E.T. specific surfaces. It has a photocatalytic activity greater than that of a monodisperse photocatalyst with a single range of B.E.T. specific surface, and thus permits, in association with a conventional hydraulic binder, to obtain construction and repair materials whose aptitude for self cleaning, for the reduction of odors, and for the depollution of ambient air, is considerably improved.

Abstract: The photocatalytic granular mixture for mortar and concrete includes a photocatalyst in the form of at least two granular classes with different B.E.T. specific surfaces. It has a photocatalytic activity greater than that of a monodisperse photocatalyst with a single range of B.E.T. specific surface, and thus permits, in association with a conventional hydraulic binder, to obtain construction and repair materials whose aptitude for self cleaning, for the reduction of odors, and for the depollution of ambient air, is considerably improved.