Abstract: Disclosed is a liquid foaming additive for use in mechanised excavation by a tunnel boring machine, containing 5-40% by weight of one or more surfactants, 0.01-5% by weight of one or more biopolymers, and 55-94.99% by weight of water.

Abstract: A process (10) for the sealing of joints (G) between prefabricated ashlars (C) or similar construction elements, comprising the following steps: inserting of a sealing strip (11), of plastic material, in a joint (G) between two adjacent prefabricated ashlars (C) so that the sealing strip (11), once inserted, extends along the joint (G) to be sealed; and injecting, by means of an injector tool (A), of a sealing resin (12) into the interior of the joint (G), so as to distribute, thanks to the containment and confinement action of the sealing strip (11) inserted in the joint (G), the sealing resin (12) along the extension of the joint (G) and therefore fill it; wherein the sealing strip (11) has, preferably, in section, a special configuration showing a plurality of inclined fins (11c), protruding from a central body (11b), apt to co-operate with the walls of the joint (G) in which the sealing strip (11) is inserted, so as to prevent the escape of the sealing resin (12) and the detachment of the sealing strip

Abstract: The present invention relates to a method for producing aggregates from concrete residues which are not used for construction purposes or, more generally, from cement mixtures which are unused for any reason and returned to the production facility in the truck mixer. The present invention also relates to the material obtained by said process and its use as an aggregate for concrete production or other applications.

Abstract: Disclosed is a liquid foaming additive for use in mechanised excavation by a tunnel boring machine, containing 5-40% by weight of one or more surfactants, 0.01-5% by weight of one or more biopolymers, and 55-94.99% by weight of water.

Abstract: The present invention relates to a method for producing aggregates from concrete residues which are not used for construction purposes or, more generally, from cement mixtures which are unused for any reason and returned to the production facility in the truck mixer. The present invention also relates to the material obtained by said process and its use as an aggregate for concrete production or other applications.

Abstract: The present invention describes a hardening accelerating admixture for hydraulic binders, the accelerator being based on transition metal silicate hydrates having the general formula: aMexOy bMO cAl2O3 SiO2 dH2O 1) where—Me represents a transition metal whose molar coefficient a is in a range between 0.001 and 2, preferably between 0.01 and 1; —M represents an alkaline earth metal whose molar coefficient b is in a range between 0 and 2, preferably between 0.3 and 1.6; —The molar coefficient c for Al2O3 is in a range between 0 and 2, preferably between 0.1 and 1; —H2O represents the hydration water of the silicate hydrate whose molar coefficient d can vary within a wide range between 0.5 and 20; x and y can both be equal to 1 or different, depending on the valence of the transition metal, given that the valence of the oxygen atom in the metal oxide is equal to 2.

Abstract: A method for producing aggregates from fresh cement compositions, included concrete and residual concrete is disclosed, comprising the addition of a) flash setting accelerators and b) super-absorbent polymers to fresh unset cement compositions and blending this mixture until granular materials are formed.

Abstract: A method for reducing hexavalent chromium in cement comprising the addition, to said cement, of antimony(III) compounds as reducing agents.

Abstract: A method for producing aggregates from fresh cement compositions, included concrete and residual concrete is disclosed, comprising the addition of a) flash setting accelerators and b) super-absorbent polymers to fresh unset cement compositions and blending this mixture until granular materials are formed.

Abstract: Superplasticizer for concrete and other cement mixtures, which is intrinsically low-foaming, promotes the early mechanical strength development and retains the workability of fresh concrete for longer time, obtainable by reacting acid, not neutralized, polycarboxylic polymers with monofunctional polyethers and difunctional polyethers in the absence of strong acidic catalysts.

Abstract: Process for the preparation of fluid organosilicon compounds usable in adhesive, coating and sealant formulations is described. The process includes the synthesis of organosilicon prepolymer compositions starting from unsaturated polyurethanes obtained in turn from unsaturated monoalcohol polyethers and diisocyanates with a controlled NCO/OH ratio, to which chlorosilanes are added in the presence of methyl or ethyl orthoformates.

Abstract: Process for the preparation of fluid organosilicon compounds usable in adhesive, coating and sealant formulations is described.

Abstract: A superplasticizing additive for concrete and other cementitious mixes with high retention of workability (low "slump loss") and low air-entraining effect, is made by terpolymers of a) (meth)acrylic acid and its salts, b)polyethyleneglycolmonomethylether-(meth)acrylate and c) polypropyleneglycol-di(meth)acrylate.