The present invention relates to a method and system to produce a concrete material having optimized strength and particle packing properties. The method and system includes a micro characterization step of a plurality of starting cementitious materials and at least one starting pozzolanic material to get respectively at least one cementitious material having uniform strength and at least one pozzolanic material having uniform blain fineness. Then grinding the said at least one cementitious material having uniform strength and the said at least one pozzolanic material having uniform blain fineness to get at least one cementitious material having a required Blaine fineness and at least one pozzolanic material having a required Blaine fineness. Finally preparing the said concrete material by mixing the said micro characterized cementitious materials and/or pozzolanic materials with at least one aggregate material, at least one additive material or a mixture thereof.

The invention relates to processes for making improved ultra-high performance microfiber concrete and articles made from the same. The invention includes blending first dry constituents of fine aggregate, steel fiber, and cement to yield a first homogenous dry mix, optionally adding carbon nanotubes and/or silicon carbide microinclusions, followed by blending with second dry constituents of silica fume, silica flour, and cenospheres to obtain a second homogenous dry mix, followed by adding water only, with further blending, and finally adding a superplasticizer admix and a water-reducing admix to obtain ultra high performance microfiber concrete. The invention also relates to voltage heating for curing and for creating heated UHPC articles.

A concrete or mortar composition including (i) a cementitious binder material that contains Portland cement and 1-50 wt % date palm ash relative to the total weight of the cementitious binder material, (ii) a coarse aggregate, (iii) a fine aggregate, and (iv) water, wherein the cementitious binder material is present at 200-500 kg per m.sup.3 of the concrete or mortar composition.

A concrete or mortar composition including (i) a cementitious binder material that contains Portland cement and 1-50 wt % date palm ash relative to the total weight of the cementitious binder material, (ii) a coarse aggregate, (iii) a fine aggregate, and (iv) water, wherein the cementitious binder material is present at 200-500 kg per m.sup.3 of the concrete or mortar composition.

A formulation and method for obtaining ultra-high performance concretes, which provide a concrete with good mechanical properties of, inter alia, traction, compression, deformation, durability, ductility and toughness, with reduced related costs

A seismic steel tubular column with internal local restraint and filled with high-strength compound concrete containing normal-strength demolished concrete lumps, and a construction process. The seismic column includes a steel tube (1), high-strength fresh concrete (2), normal-strength demolished concrete lumps (3), horizontal stirrups (4), and longitudinal erection bars (5). The horizontal stirrups (4) are arranged at upper and lower ends inside the steel tube (1). The high-strength fresh concrete (2) is poured and the normal-strength demolished concrete lumps (3) are put alternately inside the steel tube (1). A compressive strength of the high-strength fresh concrete (2) is 3090 MPa greater than that of the normal-strength demolished concrete lumps (3).

Methods for producing compositions that prevent, mitigate or delay the onset of corrosion of iron or steel (e.g., plain carbon steel) components used as reinforcement or otherwise at least partially embedded in carbonated concrete composite materials and objects based on carbonatable calcium silicate cement are disclosed.

Cementitious mixtures, compositions for use in cementitious mixtures, and methods of producing cementitious mixtures wherein the compositions are suitable for modifying or improving certain properties of the cementitious mixtures. The compositions include a superabsorbent polymer (SAP) hydrogel having a macromolecular network structure, and at least one pozzolanic material that is chemically incorporated into the macromolecular network structure of the SAP hydrogel.

A high-workability, fire-resistant, anti-spalling concrete composition is provided. The concrete composition has a slump value of at least approximately 150 mm, a fire-resistant period of at least 4 hours, a compressive strength of at least 120 MPa at room temperature, and a compressive strength of at least 20 MPa at 700 C. The composition includes cement, fly ash, silica fume, aggregate particles having a particle size D.sub.90 of approximately 20 mm or less and superplasticizer. The composition includes fiber additives including steel fibers in an amount ranging between approximately 0.1% and approximately 0.4% by volume of the concrete composition and polypropylene fibers having a melting point of approximately 200 C. or less in an amount ranging between approximately 0.05% and 0.3% by volume of the concrete composition. Carbon nanotubes are also present in an amount ranging between approximately 0.1% and approximately 0.3% by volume of the concrete composition.

The invention relates to a method for producing a cementitious composite, comprising: 1) a first step of conditioning silica nanoparticles, in which the nanoparticles are heated to a temperature between 85-235 C. for a sufficiently long time interval so as to obtain a maximum humidity content of 0.3% relative to the total weight of the material resulting from the first step; 2) a dry dispersion step, in which the conditioned nanoparticles in step 1) are dispersed over cement and in which inert grinding balls are used; 3) a step of conditioning the cementitious composite obtained in step 2), in which the grinding balls are separated from the cementitious composite produced. The invention also relates to the resulting composite, to cement derivatives comprising said composite, preferably mortars and concrete, to the production method thereof and to the use of these materials in industry.