This document relates to methods for providing long-term zonal isolation in oil wells using cement compositions that contain triazine-based polymeric additives. The cement compositions containing the polymeric additives exhibit increased tensile strength, elastic strength, or both, without suffering a decrease in compressive strength, as compared to the same cement without the polymeric additive.

An asphalt-cement concrete (“ACC”) interlayer formed of a plant-mix material reinforced with aramid fibers, deposited at a thickness of at least one inch (1″) over a Portland-cement concrete (“PCC”) or ACC base, can extend the service life of a hot-mix asphalt (“HMA”) surface layer installed over the interlayer by retarding or preventing “reflected” cracks—cracks in the surface layer that correspond to cracks, damage and irregularities in the PCC or ACC base. When the surface layer's useable life has expired, it can be removed and replaced, and the interlayer can continue to protect the new surface layer.

A shrinkage compensating concrete does not require restraint. The expansive forces developed during hydration compensate for concrete shrinkage, obviating the need for any added internal or external restraint element. Using this new shrinkage compensating concrete, substantially crack-free slabs may be built without using restraining steel bars, fibers, or other separate restraining element. The shrinkage compensating concrete includes a cement that develops internal expansive forces that never exceed the tensile strength of the concrete, such that the internal expansion compensates for the concrete shrinkage. The expansive cement may be an ASTMS, M or S cement, or other expansive cements may also be used.

Provided are a textile reinforced cement composite for suppressing occurrence of slipping and a crack and a manufacturing method thereof. The textile reinforced cement composite for suppressing occurrence of slipping and a crack can suppress slipping between a textile grid reinforcement and a cement composite by using an angulated filling material mixed therewith when a textile reinforced cement composite having a textile grid reinforcement embedded in a cement composite is manufactured, suppress occurrence of a crack of the cement composite, suppress occurrence of a crack of the cement composite due to a fiber bridging reaction by using organic fiber mixed therewith, induce distribution of fine cracks, suppress degradation of fluidity of the cement composite caused by mixing of the angulated filling material by using a spherical binder and a chemical admixture added thereto, and suppress slipping between the textile grid reinforcement and the cement composite by using a fine powder binder having a predetermined particle size and mixed therewith.

There is described a composition for synthetic stone. The composition having (a) 3 to 25 wt % acrylic resin, the acrylic resin having:(i) >50 upto 95 wt % methyl methacrylate and methyl methacrylate monomer residues, (ii) 4 to 40 wt % higher boiling point mono(alk)acrylate monomer, (iii) optionally, 0 to 10 wt % other acrylate or vinyl comonomer residues, and(iv) a crosslinking agent. The MMA residues of component (a)(i) are present in the acrylic resin in the form of a MMA residue containing (co)polymer, comprising at least 80% residues of MMA by weight of the (co)polymer. The composition further having (b) 70 to 95 wt % filler; and (c) optionally, a coupling agent. The composition being especially useful for the manufacture of synthetic stone for use in outdoor applications.

This document relates to methods for providing long-term zonal isolation in oil wells using cement compositions that contain triazine-based polymeric additives. The cement compositions containing the polymeric additives exhibit increased tensile strength, elastic strength, or both, without suffering a decrease in compressive strength, as compared to the same cement without the polymeric additive.

Cement slurries, cured cements, and methods of making cured cement and methods of using cement slurries are provided. The cement slurries have, among other attributes, improved elasticity and self-healing properties and may be used, for instance, in the oil and gas drilling industry. The cement slurry comprises water, a cement precursor material, and a block copolymer composition. The block copolymer composition has at least one copolymer backbone, with each copolymer backbone comprising at least two hard segments. Furthermore, a soft segment is disposed between the at least two hard segments. The copolymer backbone has at least one anhydride group grafted onto the soft segment, and the anhydride group is crosslinked by an aminosilane crosslinker.

Disclosed herein are composite materials, including composite building materials, comprising a polyurethane composite core in physical communication with a cementitious layer. Also disclosed are methods for producing the composite materials.

Cement slurries, cured cements, and methods of making cured cement and methods of using cement slurries are provided. The cement slurries have, among other attributes, improved elasticity and self-healing properties and may be used, for instance, in the oil and gas drilling industry. The cement slurry comprises water, a cement precursor material, and a block copolymer composition. The block copolymer composition has at least one copolymer backbone, with each copolymer backbone comprising at least two hard segments. Furthermore, a soft segment is disposed between the at least two hard segments. The copolymer backbone has at least one anhydride group grafted onto the soft segment, and the anhydride group is crosslinked by an aminosilane crosslinker.

A cement composition is disclosed containing: cement; cellulose nanofibers; and water, wherein a mass ratio of the water to cement is 0.4 or less. The cement is preferably Portland cement. It is preferred that the Portland cement is high-early-strength Portland cement, and that a mass ratio of fine aggregate to the high-early-strength Portland cement is 2.0 or less. A unit amount of cellulose nanofibers in the cement composition can be 0.1 kg/m.sup.3 to 15 kg/m.sup.3 Furthermore, a hardened body of the cement composition is disclosed, wherein a ratio of a splitting tensile strength of the hardened body at a material age of 91 days obtained by curing in air, to the splitting tensile strength of the hardened body at the material age if 91 days obtained by curing in water is 0.90 or more and 1.10 or less, the splitting tensile strength being measured in accordance with JIS-A-1113 (2006).