A method of producing high-strength cementitious product from raw fly ash by mixing the raw fly ash with a lithium compound, whereby milling of the raw fly ash to achieve requisite strength is unnecessary. It has now been found that by adding as little as 0.1% of lithium chloride to raw untreated Class C fly ash, one can achieve improved seven-day and twenty-eight-day compressive strength. At the very least, raw lithium treated Class C fly ash may be used at lower total cementitious content per yard of concrete as opposed to Ordinary Portland Cement (OPC) for improved compressive strength.

The present invention relates to a method for impregnating concrete with a non-aqueous electrolyte characterized in that an electric field is applied between electrodes mounted on the concrete surface and/or embedded in the concrete such that the non-aqueous electrolyte migrates into the concrete. Preferably, lithium ions are dissolved in the non-aqueous electrolyte.

It has been unexpectedly discovered that the addition of a natural or other pozzolan to non-spec fly ash significantly improves the properties of the non-spec fly ash to the extent it can be certified under ASTM C618 and AASHTO 295, as either a Class F or Class C fly ash. The natural pozzolan may be a volcanic ejecta, such as pumice or perlite. Other pozzolans may also be used for this beneficiation process. Many pozzolans are experimentally tested and may be used to beneficiate non-spec fly ash into certifiable Class F fly ash. Additionally, this disclosure provides a method of converting a Class C fly ash to a more valuable Class F fly ash. This discovery will extend diminishing Class F fly ash supplies and turn non-spec fly ash waste streams into valuable, certified fly ash pozzolan which will protect and enhance concrete, mortars and grouts.

A lightweight concrete formulation containing Portland cement, aggregate, glass particles, water and metakaolin. At least 80% of the glass particles have a grain size of less than 2 mm. The glass particles contribute between 3% and 20% of the total weight of the concrete formulation. The metakaolin contributes between 4% and 12% of the total weight of the concrete formulation. The glass particles are preferably expanded glass particles. Also provided is a lightweight grout formulation containing Portland cement, glass particles, water and metakaolin. At least 80% of the glass particles have a grain size of less than 2 mm. The glass particles contribute between 3% and 15% of the total weight of the grout formulation. The metakaolin contributes between 7% and 15% of the total weight of the grout formulation.

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

It has been unexpectedly discovered that the addition of a natural or other pozzolan to non-spec fly ash significantly improves the properties of the non-spec fly ash to the extent it can be certified under ASTM C618 and AASHTO 295, as either a Class F or Class C fly ash. The natural pozzolan may be a volcanic ejecta, such as pumice or perlite. Other pozzolans may also be used for this beneficiation process. Many pozzolans are experimentally tested and may be used to beneficiate non-spec fly ash into certifiable Class F fly ash. Additionally, this disclosure provides a method of converting a Class C fly ash to a more valuable Class F fly ash. This discovery will extend diminishing Class F fly ash supplies and turn non-spec fly ash waste streams into valuable, certified fly ash pozzolan which will protect and enhance concrete, mortars and grouts.

A blended cementitious mixture is disclosed, the blended cementitious mixture comprising: a cement included in an amount corresponding to greater than 3% and less than 40% by mass of powders in the cementitious mixture; supplemental cementitious materials included in an amount corresponding to greater than 50% and less than 90% by mass of powders in the cementitious mixture and a carbonate source included in an amount less than or equal to 20% by mass of powders in the cementitious mixture. The cementitious mixture can be mixed with concrete sand, water, chemical admixtures and coarse aggregates and cured to form concrete.

A lightweight concrete formulation containing Portland cement, aggregate, glass particles, water and metakaolin. At least 80% of the glass particles have a grain size of less than 2 mm. The glass particles contribute between 3% and 20% of the total weight of the concrete formulation. The metakaolin contributes between 4% and 12% of the total weight of the concrete formulation. The glass particles are preferably expanded glass particles. Also provided is a lightweight grout formulation containing Portland cement, glass particles, water and metakaolin. At least 80% of the glass particles have a grain size of less than 2 mm. The glass particles contribute between 3% and 15% of the total weight of the grout formulation. The metakaolin contributes between 7% and 15% of the total weight of the grout formulation.

A method of producing high strength cementitious product from raw fly ash by mixing the raw fly ash with a lithium compound, whereby milling of the raw fly ash to achieve requisite strength is unnecessary. It has now been found that by adding as little as 0.1% of lithium chloride to raw untreated Class C fly ash one can achieve improved seven day and twenty-eight day compressive strength. At the very least, raw lithium treated Class C fly ash may be used at lower total cementitious content per yard of concrete as opposed to ordinary Portland Cement for improved compressive strength.

It has been unexpectedly discovered that the addition of a natural or other pozzolan to non-spec fly ash significantly improves the properties of the non-spec fly ash to the extent it can be certified under ASTM C618 and AASHTO 295, as either a Class F or Class C fly ash. The natural pozzolan may be a volcanic ejecta, such as pumice or perlite. Other pozzolans may also be used for this beneficiation process. Many pozzolans are experimentally tested and may be used to beneficiate non-spec fly ash into certifiable Class F fly ash. Additionally, this disclosure provides a method of converting a Class C fly ash to a more valuable Class F fly ash. This discovery will extend diminishing Class F fly ash supplies and turn non-spec fly ash waste streams into valuable, certified fly ash pozzolan which will protect and enhance concrete, mortars and grouts.