Method and apparatus for transforming organic and inorganic solid urban waste into aggregates, comprising an extruding machine connected to a reactor. The extruding machine is formed by an extrusion cylinder through which a piston circulates inside an extrusion cavity, which comprises three sections and is fed with a parget obtained after pre-processing the waste. The end of the third section is connected to the reactor through an opening. The reactors longitudinal shaft is formed by a rotatory steel shaft in which some steel blades are arranged, whose ends play the roles of cutting, hammering, punching and hydraulic helix as they rotate. Between the end of the blades and the wall of the reactor, there is a clearance of more than 0.1 mm of thickness. The reactor has a discharge valve to discharge the parget present in the boundary area through some openings, once it has been processed by a series of pressure, vibration energy and decompression cycles.

A foaming agent, more particularly for the foaming of a building material/binder paste for producing pory lightweight-construction and insulating materials, is improved in terms of its stability and usefulness at relatively low outdoor temperatures. The foaming agent in the form of an aqueous-organic solution comprises or consists to an extent of at least 85 wt % of the following constituents: a) a surfactant component which comprises at least one foam-forming ionic surfactant, b) a fatty alcohol component which comprises at least one fatty alcohol and at least one ethoxylated fatty alcohol in a FA/FAEO mixing ratio of 95:5 to 0:100, c) a glycol component which comprises at least one constituent of the group of alkyl glycols, alkylene glycols up to C6 alkyl, diglycols, especially alkyl diglycols and diglycol ethers, and water.

The invention discloses a strontium ferrite-based sacrificial mortar and its preparation method, the strontium ferrite-based sacrificial mortar mainly comprises 720-1000 parts of sulphoaluminate cement, 100-300 parts of strontium ferrite, 600-650 parts of quartz sand, 400-450 parts of water and 0.01-35 parts of superplasticizer. The preparation process is simple, and the strontium ferrite-based sacrificial mortar can be prepared by using a conventional forced single horizontal shaft concrete mixer. The obtained mortar has excellent working performance, compressive strength and corrosion resistance. It can be used in the current third and future fourth generation nuclear power plant core catchers, and has obvious engineering application value.

The present invention provides methods, admixture compositions for treating clay-bearing aggregates used for construction purposes, and aggregate compositions for construction purposes. The clay-bearing aggregates are treated with a cationic copolymer made from two and preferably three different monomer components. Cementitious compositions containing the treated aggregates are also described.

A fluidizing composition in the form of a liquid or in the form of a powder including at least one superplasticizer chosen from polycarboxylate ethers, characterized in that it includes from 1 to 20 parts by weight of at least one aromatic hydrocarbon sulfonic acid or one of its salts chosen from alkali salts, alkaline-earth salts or one of their mixtures, for 100 parts by weight of the superplasticizer. A method for preparing such fluidizing composition, a dry mortar incorporating the fluidizing composition, as well as plasters prepared from the dry mortar are also described.

The present invention relates to fiber cement flooring products. In particular, the present invention provides fiber cement flooring products, at least comprising cement and fibers, characterized in that these fiber cement flooring products comprise amorphous silica in an amount of between about 2 weight % and about 15 weight % compared to the total dry weight of the fiber cement composition of said fiber cement flooring product. The present invention further relates to methods for the production of such fiber cement flooring products as well as uses of such fiber cement flooring products in the building industry. The present invention further relates to fiber cement formulations and fiber cement materials, which are suitable for the production of fiber cement products for flooring applications.

A cementitious multi-component mortar system contains finely ground granulated blast-furnace slag with a grinding fineness in the range of from 5,000 to 15,000 cm.sup.2/g. The cementitious multi-component mortar system can be used as an inorganic chemical fastening system for anchoring elements in mineral substrates.

A free-flowing powder composition includes at least one substrate having pores and an external surface between said pores, said surface functionalized with at least one accelerator for a hydraulic setting composition, said accelerator being liquid, hygroscopic, or deliquescent, and wherein after 15 minutes of immersion of free-flowing powder composition in water at 20° C. at least 80% in weight of said accelerator is solubilized, said free-flowing powder composition being immersed in an amount of water sufficient so that the saturation concentration of said accelerator cannot be reached. There is also a method for preparing said free-flowing powder composition. The use of said free-flowing powder composition as an additive for mortar or concrete composition provides an accelerating effect, an anti-ageing effect and an anti-dusting effect. A dry mortar or concrete composition includes a hydraulic binder, said free-flowing powder composition and a granulate, wet mortar or concrete composition and hardened body obtained therefrom.

An anticorrosion agent comprising (A) an organosilicon compound of formula (1)
R.sup.1—Si—(OR.sup.2).sub.3  (1)
and (B) an amine compound of formula (2) ##STR00001##
and/or an amine compound of formula (3) ##STR00002##
is applied to steel-reinforced concrete to prevent corrosion of the steel reinforcement.

The present invention provides a wet press process and admixture components for making concrete slabs (flags) (16), curb (kerb) units, panels, boards, and other flat shapes, whereby colloidal silica and at least one alkanolamine and optional rheology control components are employed to provide an ideal combination of pressing time, green strength, surface definition, stack-ability, final concrete strength, and permeability. Stack-ability can be expressed in terms of minimum deflection or non-eccentricity of the units while standing on thickness edges at distances apart less than width or standing height. A wet press process typically involves introducing a highly fluid concrete mix into a mold (10,12), applying hydraulic pressure to consolidate the concrete (e.g., 1000-3000 PSI) and to extract excess water, removing the pressed concrete (16) while in a green state from the mold (10,12), and then standing the slab (16) units immediately upon removal from the mold (10,12) while in a green state, on an edge adjacent to but spaced apart from other edge-standing units. In further embodiments, rounded aggregates such as naturally occurring sand and/or gravel obtained from local sources can be incorporated into the concrete slabs without defeating (vertical) stack-ability in the green state.