Electromagnetically-induced cement concrete crack self-healing diisocyanate microcapsules include raw materials, in parts by weight, comprising 15-55 parts of petroleum resin, 5-10 parts of paraffin, 5-10 parts of polyethylene wax, 3-10 parts of magnetic iron powder and 20-67 parts of diisocyanate. The diisocyanate microcapsules use the diisocyanate as a core material, and the petroleum resin/paraffin/polyethylene wax/magnetic iron powder mixture as the shell of the capsule. When micro cracks occur in the concrete, the crack propagation can break partial of the microcapsule inside, the diisocyanate inside the microcapsules flows out and diffuses into the crack and is subjected to a solidifying reaction with water in the concrete, so that the crack is repaired in time; and for the microcapsules that are not broken by cracks, external electromagnetic field can be applied to melt the shell to release the diisocyanate inside, thereby diffusing into cracks and solidify with water to repair them.

Provided is a cement additive that can significantly improve the strength of a cured product of a cement composition over a long time period. Also provided is a cement composition including such cement additive. The cement additive of the present invention includes: a compound (A) having a weight-average molecular weight of more than 3,000, and having a structure in which 5 moles or more of an alkylene oxide is added to 1 mole of a polyhydric alcohol; and an alkanolamine compound (B).

Cementitious compositions and methods for preparing and using the cementitious compositions to yield hardened concrete. The cementitious compositions yield hardened concrete having reduced or attenuated water vapor emission and lower internal relative humidity (IRH). Cementitious compositions are characterized by the property of rapid surface drying while maintaining good workability, particularly when using porous lightweight aggregates that absorb substantial amounts of water. Methods of decreasing water availability and increasing surface drying of concrete, including lightweight concrete, are provided. A water soluble ionic salt may be used to sequester water within the pores and capillaries of the cement paste and/or porous lightweight aggreate by modifying the colligative propertie of pore water. The salt may be added directly to concrete or the concrete mix water, or, alternatively, aggregates may be infused with a water-salt solution to provide treated porous aggregates having improved water saturation and water retention.

The present invention provides pourable aqueous dispersion compositions of (a) one or more cellulose ethers and (b) one or more superplasticizers stably suspended in an aqueous dispersion of (c) one or more stabilizers in the form of a colloidal dispersion, further containing (d) one or more monovalent salts, such as an alkali metal salt. The minimum total amount of the cellulose ether, as solids in the pourable aqueous dispersion is 8 wt. % or, preferably, 12 wt. % or, preferably, 14 wt. % and the solids weight ratio of total cellulose ether to salt is close to 1:1, ranging, for example, from 0.7:1 to 1.4:1. Further, the amounts of the (a) one or more cellulose ethers and the (b) one or more superplasticizers enable the provision of pourable aqueous dispersion compositions effective for use in cement applications by simple dilution with water.

The present invention provides pourable aqueous dispersion compositions of (a) one or more cellulose ethers and (b) one or more superplasticizers stably suspended in an aqueous dispersion of (c) one or more stabilizers in the form of a colloidal dispersion, further containing (d) one or more monovalent salts, such as an alkali metal salt. The minimum total amount of the cellulose ether, as solids in the pourable aqueous dispersion is 8 wt. % or, preferably, 12 wt. % or, preferably, 14 wt. % and the solids weight ratio of total cellulose ether to salt is close to 1:1, ranging, for example, from 0.7:1 to 1.4:1. Further, the amounts of the (a) one or more cellulose ethers and the (b) one or more superplasticizers enable the provision of pourable aqueous dispersion compositions effective for use in cement applications by simple dilution with water.

A composition includes one hydraulic binder including at least one clinker, and at least one branched polyalkyleneimine, having a molecular weight between 400 g/mol and 1,000,000 g/mol, at a weight ratio polyalkyleneimine(s)/binder between 0.05% and 5.0%.

A composition includes one hydraulic binder including at least one clinker, and at least one branched polyalkyleneimine, having a molecular weight between 400 g/mol and 1,000,000 g/mol, at a weight ratio polyalkyleneimine(s)/binder between 0.05% and 5.0%.

Various embodiments disclosed relate to compositions including acidic chelator or salt or ester thereof for treatment of subterranean formations including one or more fractures. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in the subterranean formation a composition including an acidic chelator or a salt or ester thereof. The subterranean formation includes one or more fractures.

Various embodiments disclosed relate to compositions including acidic chelator or salt or ester thereof for treatment of subterranean formations including one or more fractures. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in the subterranean formation a composition including an acidic chelator or a salt or ester thereof. The subterranean formation includes one or more fractures.

A castable construction material with controlled flow and workability retention comprising (a) a binder comprising from 75% to 100% by weight of fly ashes comprising from 1.5% to 35% by weight of Ca O and a Lost on Ignition (LOI) value from 0.5% to 5.5% by weight, (b) an activator comprising an alkali hydroxide and an alkali silicate, wherein the activator is from 3% to 25% by weight with respect to the castable construction material, (c) sand, (d) fine aggregates, (e) coarse aggregates, (f) free water and (g) a workability retention agent wherein selected from the group consisting of polycarboxylate ether polymer (PCE), polyamines, polyethylene imines, polyacrylamides, polyacrylate (EO, PO) ester, polymethacrylate (EO, PO) ester, polyammonium derivatives and co-polymers thereof, polydiallyldimethylammonium chloride, benzalkonium chlorides, substituted quaternary ammonium salts, chitosans, caseins and cationically modified colloidal silica.