A hydraulic composition includes in relative parts by mass with respect to first Portland cement: 100 parts of a first Portland cement the particles of which have a D50 between 10 and 25 μm; from 25 to 76 parts of a second Portland cement the particles of which have a D50 between 0.5 and 6 μm; from 85 to 200 parts of sand; water; the water content being such that the hydraulic composition includes from 170 to 250 kg of water per cubic metre of hydraulic composition; the volume distribution of particle size of the first Portland cement and of the second Portland cement being further such that the ratio D50 of the first Portland cement/D50 of the second Portland cement is greater than 2.

There is described a high-strength concrete generally having: about 100 parts by weight of cement; about 60 to about 360 parts by weight of fine aggregates; about 90 to about 230 parts by weight of mineral powder having a diameter D50 below 150 .Math.m; about 0.1 to about 25 parts by weight of superplasticizer; and about 20 to about 65 parts by weight of water, the high-strength concrete has a cement content less than about 500 kg/m.sup.3 and having a compressive strength after 28 curing days of about 55 MPa or greater.

Alumina-modified colloidal silica nanoparticles mitigate Alkali Silica Reaction (ASR) in cementitious compositions. Additives containing the nanoparticles are used in methods of reducing ASR in concrete and to form cementitious compositions. Cementitious products, such as concrete, made by these methods are described herein.

The present invention relates to a material system for 3D printing, to a 3D printing process using a lignin-containing component or derivatives thereof or modified lignins, to soluble moldings that are produced by a powder-based additive layer manufacturing process and to the use of the moldings.

Embodiments of the invention relate to concrete admixtures, provide a phosphonato block polymer, a preparation method and an application. The method includes: the phosphonato block polymer prepared by copolycondensating an ether-type segment A, a phosphonato segment B, and a third part of aldehyde C. The ether-type segment A is obtained by polycondensating a polyether monomer and a first part of aldehyde C. The phosphonato segment B is obtained by polycondensating a monomer b containing phosphonato, a monomer c, and a second part of aldehyde C in an aprotic weak polar solvent E. By preparing a block polymer using arylalkane as a main chain and using a phosphonic acid or phosphinic acid functional group as an adsorption group, the invention improves the resistance of the block polymer to sulfate and clay interference, and can achieve initial high dispersion of concrete with a low water-cement ratio and decreasing of the system viscosity.

A structural barrier and energy absorbing device comprises a plurality of structural elements. The structural element alone or in a plurality may serve as a traversal impediment or energy absorbing device, such as a pedestrian barrier, vehicular barrier, anti-tank obstacle, ballistic barrier, or the like. The structural element may be a tetrapod such that it comprises an element body having four extension portions that extend outwardly from the interior center to a distal end, such that the structural element maintains an identical orientation and a low center of gravity in each of four resting positions. The structural element may be a solid-state structural element comprised of a particular material or a portable and collapsible structural element wherein the element body comprises an outer skin defining an interior void space, such that during set-up or installation the interior void space may be filled with a filler substance onsite.

An anti-blast concrete and a method of fabricating an anti-blast structure member using such anti-blast concrete are disclosed. The composition of the anti-blast concrete according to the invention includes, in parts by weight, 1.0 part by weight of cement, 1.0 to 2.5 parts by weight of fine aggregates, 1.0 to 2.5 parts by weight of coarse aggregates, and a plurality of reinforcing fibers. The weight ratio of the reinforcing fibers to the cement ranges from 0.5% to 3%. The plurality of reinforcing fibers are a plurality of carbon fibers or a plurality of aramid fibers. A test body, made of the anti-blast concrete of the invention, has an average number of times of repeated impacts at an impact energy of 49.0 Joules equal to or larger than 41 times at 28 days of age.

Class C fly ash-based cementitious materials, concretes, and related techniques are disclosed. In accordance with some embodiments, an activated class C fly ash-based cementitious material may be produced by intergrinding class C fly ash (e.g., classified to remove quartz and/or other contaminants and, thus, increase the reactive materials present), an activator, sodium citrate, borax, and a polycarboxylate material. The class C fly ash may have an amorphous glass content of about 60 wt % or more, a calcium oxide (CaO.sub.2) content of about 20 wt % or more, and a quartz content of about 10 wt % or less. The activator may be a chemical which reacts with class C fly ash to form strätlingite structures therein when introduced with water. In some cases, the cementitious material may be provided as an all-in-one powder blend. In some case, techniques disclosed herein may be utilized in providing a fast-setting flowable fill material.

It is disclosed the use of amorphous silica reagent produced from serpentine as pozzolane additive material, and more particularly a concrete mixture, such as high performance and ultra-high performance concrete, comprising a hydraulic binder; sand; aggregates, chemical admixture, mineral admixture as silica fume and an amorphous silica reagent (AmSR), wherein the AmSR is admixed for example with General Use Portland Cement and provides synergistic effect when combined with silica fume.

The invention relates to a mineral binder suitable for use in binding aggregate in a mineral mortar or concrete mixture, said binder comprising the following components:

a) at least 40 wt % of calcined kaolinitic clay and ultrafine crushed CDW,
wherein the ratio between calcined clay and ultrafine crushed CDW is between 3:7 and 1:1 (w/w),
b) optionally 2-50 wt. % of a chemical activator; and
wherein the calcined kaolinitic clay, the ultrafine crushed CDW and the optionally present chemical activator are present in a combined amount of at least 90 wt. %, based on the total weight of the binder. The invention further relates to mineral mortar or concrete mixtures based on this mineral binder, as well as building units made from these mixtures.