A cement composition for use in a well that penetrates a subterranean formation comprising: cement; water; and an additive comprising zirconium dioxide, wherein at least a portion of the zirconium dioxide is in a metastable tetragonal phase, and wherein some or all of the zirconium dioxide that is in the metastable tetragonal phase transforms to a stable monoclinic phase after a stress is applied to the cement composition. The additive also reduces the dimensions of a crack located within the set cement composition. A method of cementing in a subterranean formation comprising: introducing a cement composition into the subterranean formation.

Disclosed herein are fire resistant compositions and articles, for example, in the form of boards, insulation, sheeting, blocks, panels and similar materials of construction. Also disclosed are methods of preparing fire resistant compositions and articles and methods of use thereof.

Disclosed herein are fire resistant compositions and articles, for example, in the form of boards, insulation, sheeting, blocks, panels and similar materials of construction. Also disclosed are methods of preparing fire resistant compositions and articles and methods of use thereof.

A cement composition for use in a well that penetrates a subterranean formation comprising: cement; water; an environmentally-friendly curable resin having two or more epoxy functional groups; and a curing agent that causes the curable resin to cure when in contact with the curing agent. A method of cementing in a subterranean formation comprising: introducing the cement composition into the subterranean formation; and allowing the cement composition to set after introduction.

A cement composition for use in a well that penetrates a subterranean formation comprising: cement; water; an environmentally-friendly curable resin having two or more epoxy functional groups; and a curing agent that causes the curable resin to cure when in contact with the curing agent. A method of cementing in a subterranean formation comprising: introducing the cement composition into the subterranean formation; and allowing the cement composition to set after introduction.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

A manufacturing process of a cement product includes: (1) incorporating at least one additive into a high-alumina cement composition, wherein the at least one additive is selected from nitrate-containing salts, nitrite-containing salts, carbonate-containing salts, sulfate-containing salts, chloride-containing salts, and hydroxide-containing salts; and (2) curing the high-alumina cement composition to form the cement product.