Methods of using extended-life cement compositions are disclosed. A method comprises providing an extended-life cement composition comprising calcium-aluminate cement, water, and a cement set retarder. The method additionally comprises mixing the extended-life cement composition with a cement set activator to activate the extended-life cement composition. The method further comprises Introducing the activated extended-life cement composition into a subterranean formation and allowing the activated extended-life cement composition to set in the subterranean formation; wherein the activated extended-life cement composition has a thickening time of greater than about two hours.

A structural lightweight concrete composition comprising cement, a fine aggregate such as sand, a natural coarse aggregates, such as limestone, scoria or perlite or mixtures thereof, a synthetic coarse aggregate comprising a polymeric material, such as polypropylene beads, an industrial waste byproduct in the form of fine particles, such as silica fume or heavy oil ash, a superplasticizer, such as a polycarboxylate ether and water demonstrating lower thermal conductivity and sufficient compressive strength. Concrete products made therefrom and methods for producing such products are also provided.

Provided is a cement composition that has high fluidity (for example, a 0-drop flow value of 200 mm or more) before curing and exhibits high compressive strength (for example, 320 N/mm.sup.2 or more) after curing. The cement composition includes a cement, a silica fume having a BET specific surface area of from 10 m.sup.2/g to 25 m.sup.2/g, an inorganic powder having a 50% cumulative particle size of from 0.8 μm to 5 μm, a fine aggregate having a maximum particle size of 1.2 mm or less, a water reducing agent, an antifoaming agent, and water. The ratio of the cement is from 55 vol % to 65 vol %, the ratio of the silica fume is from 5 vol % to 25 vol %, and the ratio of the inorganic powder is from 15 vol % to 35 vol % in the total amount of 100 vol % of the cement, the silica fume, and the inorganic powder.

Provided is a cement composition that has high fluidity (for example, a 0-drop flow value of 200 mm or more) before curing and exhibits high compressive strength (for example, 320 N/mm.sup.2 or more) after curing. The cement composition includes a cement, a silica fume having a BET specific surface area of from 10 m.sup.2/g to 25 m.sup.2/g, an inorganic powder having a 50% cumulative particle size of from 0.8 μm to 5 μm, a fine aggregate having a maximum particle size of 1.2 mm or less, a water reducing agent, an antifoaming agent, and water. The ratio of the cement is from 55 vol % to 65 vol %, the ratio of the silica fume is from 5 vol % to 25 vol %, and the ratio of the inorganic powder is from 15 vol % to 35 vol % in the total amount of 100 vol % of the cement, the silica fume, and the inorganic powder.

Methods for treating and restoring zonal isolation in a subterranean well involve the use of a well treatment tool that may drill one or more holes in casing and inject a treatment fluid that may seal cracks or fissures in the cement sheath behind the casing. Microannuli may also be sealed. The treatment fluids may be solids free or in the form of suspensions containing solids having a particle size between 1 nm and 100 nm.

A concrete mixture is provided. The mixture includes cement powder, a plant biomaterial in a solid form, wherein the plant biomaterial does not comprise ash, and concrete aggregate, wherein a ratio of cement powder to the biomaterial ranges from 10:1 to 100:1. Methods of controlling concrete setting by adding a plant biomaterial in a solid form to a concrete mixture are also provided.

The invention relates to a method (100) for selecting the composition of a construction material including an excavated clay soil, said construction material composition to include deflocculating agent and activating agent quantities adapted to the excavated clay soil, said method including a step of receiving (130) a measured value of at least one physicochemical property of an excavated clay soil, and a step of selecting (170) a deflocculating agent quantity and an activating agent quantity adapted to the excavated clay soil. In addition, the invention also relates to a method (200) for calibrating a calculation algorithm for determining the composition of a site construction material, to a construction material formed from an excavated clay soil, and to a system (400) for preparing a construction material including an excavated clay soil.

Water-based paint is used as a sacrificial agent to reduce the detrimental effect of carbon-containing fly ash on the entrainment of air in concrete. The invention provides a composition for reducing the effect of carbon contained in fly ash on air entrainment in cementitious mixtures comprising water, cement, fly ash and entrained air. The composition comprises water-based paint and one or more of pulverized or un-pulverized pozzolan, pulverized or un-pulverized cementitious solids, a superplasticizer, a defoamer, an air-entraining admixture, a water-reducing admixture, a retarding admixture, an accelerating admixture, a hydration control admixture and a rheology modifying admixture. The invention also provides a method of reducing the effect of carbon on air entrainment in carbon-containing fly ash, comprising mixing the fly ash with water-based paint.

The present disclosure relates to the technical field of solid waste recycling and fabricated buildings, and provides a solid waste large-mixing-amount concrete prefabricated laminated slab and a preparation method thereof. The solid waste large-mixing-amount concrete prefabricated laminated slab provided by the present disclosure comprises a prefabricated layer and a laminated layer. Transverse grooves and longitudinal grooves are formed in the surface of the prefabricated layer. During application, the grooves can be used for erecting pipelines, the contact area of the prefabricated layer and the laminated layer can also be increased, the combined effect of new concrete and old concrete is improved, the integrity of a floor slab is enhanced, and the effect of improving the overall stress capacity of the floor slab is achieved.

The present disclosure relates to the technical field of solid waste recycling and fabricated buildings, and provides a solid waste large-mixing-amount concrete prefabricated laminated slab and a preparation method thereof. The solid waste large-mixing-amount concrete prefabricated laminated slab provided by the present disclosure comprises a prefabricated layer and a laminated layer. Transverse grooves and longitudinal grooves are formed in the surface of the prefabricated layer. During application, the grooves can be used for erecting pipelines, the contact area of the prefabricated layer and the laminated layer can also be increased, the combined effect of new concrete and old concrete is improved, the integrity of a floor slab is enhanced, and the effect of improving the overall stress capacity of the floor slab is achieved.