A refractory composition is formed by preparing a set retarded fresh cementitious composition formed from a class C fly ash, a set retardant such as boric acid, and an alkali activator such as an alkali metal citrate salt, and contacting the set-retarded fresh cementitious composition with a pH regulator, such as an alkali metal hydroxide or alkali metal carbonate. The set retarded mixture provides workability and avoids equipment fouling caused by premature setting, while the alkali activator provides rapid setting when desired. The cementitious composition is shaped into a brick, panel, slab, concrete fire log, or the like and allowed to harden. The hardened cementitious composition can be heated to form a dried cementitious composition, and further heated to produce a high strength refractory composition. Fibers and/or aggregates may be included.

Disclosed herein are cement compositions and methods of using cement compositions in subterranean formations. An embodiment discloses a method of formulating a cement composition. The method may comprise measuring surface area of a group of pozzolans, wherein the smallest measured surface area of the group of pozzolans and the largest measured surface area of the group of pozzolans vary by about 50% or greater. The method may further comprise selecting one or more pozzolans from the group of pozzolans. The method may further comprise adding components comprising lime and water to the selected one or more pozzolans to form a cement composition.

Disclosed herein are cement compositions and methods of using cement compositions in subterranean formations. An embodiment discloses a method of formulating a cement composition. The method may comprise measuring surface area of a group of pozzolans, wherein the smallest measured surface area of the group of pozzolans and the largest measured surface area of the group of pozzolans vary by about 50% or greater. The method may further comprise selecting one or more pozzolans from the group of pozzolans. The method may further comprise adding components comprising lime and water to the selected one or more pozzolans to form a cement composition.

The present disclosure provides a geopolymer composition having a controllable setting time comprising: at least one reactive aluminosilicate; at least one retarder; and at least one alkali silicate activator solution.

A fastening system for chemically fastening an anchor, the fastening system including a chemical anchor that is a ready-for-use two-component mortar system based on albuminous cement, and an anchor rod comprising an attachment region and an anchoring region. The anchor rod is insertable into a borehole and has a profiled section including a plurality of expansion sections disposed axially in a row which are conically shaped.

A variety of methods and compositions are disclosed, including, in one embodiment, a method of cementing in a subterranean formation, comprising: providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; activating the set-delayed cement composition; introducing the set-delayed cement composition into a subterranean formation; and allowing the set-delayed cement composition to set in the subterranean formation.

A variety of methods and compositions are disclosed, including, in one embodiment, a method of cementing in a subterranean formation, comprising: providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; activating the set-delayed cement composition; introducing the set-delayed cement composition into a subterranean formation; and allowing the set-delayed cement composition to set in the subterranean formation.

Disclosed herein is a method of cementing a surface with a set-delayed cement composition. The method comprises providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder. The method further comprises placing the set-delayed cement composition into or onto a surface to be cemented and allowing the set-delayed cement composition to set in the surface.

Disclosed herein is a method of cementing a surface with a set-delayed cement composition. The method comprises providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder. The method further comprises placing the set-delayed cement composition into or onto a surface to be cemented and allowing the set-delayed cement composition to set in the surface.

Disclosed is a method of forming a set cement shape. The method comprises providing a set-delayed cement composition comprising water, pumice, hydrated lime, and a set retarder; forming the set-delayed cement composition into a shape; and allowing the shaped set-delayed cement composition to set.