A nanozeolite modified green concrete contains alkali-activated natural pozzolan. Natural pozzolan is a green and sustainable material, potentially useful in green concrete, e.g., to curb greenhouse gas emissions associated with ordinary Portland cement production. Nanozeolite (NZ) is present as an additive to the green concrete, e.g., at 3 to 5 wt. %, of natural pozzolan to improve strength development and microstructural properties, resulting in superior strength and denser microstructure compared to a green concrete without nanozeolite.

A nanozeolite modified green concrete contains alkali-activated natural pozzolan. Natural pozzolan is a green and sustainable material, potentially useful in green concrete, e.g., to curb greenhouse gas emissions associated with ordinary Portland cement production. Nanozeolite (NZ) is present as an additive to the green concrete, e.g., at 3 to 5 wt. %, of natural pozzolan to improve strength development and microstructural properties, resulting in superior strength and denser microstructure compared to a green concrete without nanozeolite.

It has been unexpectedly discovered that the addition of a natural or other pozzolan to non-spec coal ash significantly improves the properties of the non-spec coal ash to the extent it can be certified under ASTM C618 and AASHTO 295, as either a Class F or Class C coal 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 coal ash into certifiable Class F coal ash. Additionally, this disclosure provides a method of converting a Class C coal ash to a more valuable Class F coal ash. This discovery will extend diminishing Class F coal ash supplies and turn non-spec coal ash waste streams into valuable, certified coal ash pozzolan which will protect and enhance concrete, mortars and grouts.

It has been unexpectedly discovered that the addition of a natural or other pozzolan to non-spec coal ash significantly improves the properties of the non-spec coal ash to the extent it can be certified under ASTM C618 and AASHTO 295, as either a Class F or Class C coal 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 coal ash into certifiable Class F coal ash. Additionally, this disclosure provides a method of converting a Class C coal ash to a more valuable Class F coal ash. This discovery will extend diminishing Class F coal ash supplies and turn non-spec coal ash waste streams into valuable, certified coal ash pozzolan which will protect and enhance concrete, mortars and grouts.

The present invention relates to a composition in the form of a mixture comprising F-type fly ash, a reactive silicon source, a setting accelerator and a light aggregate with a density of less than 900 kg/m.sup.3 and a mechanical strength of at least 0.08 MPa, and the uses thereof to obtain light and fireproof construction materials.

The present invention relates to a composition in the form of a mixture comprising F-type fly ash, a reactive silicon source, a setting accelerator and a light aggregate with a density of less than 900 kg/m.sup.3 and a mechanical strength of at least 0.08 MPa, and the uses thereof to obtain light and fireproof construction materials.

A low-density, high-strength concrete composition that is lightweight and self-compacting or non-self-compacting, with a low weight-fraction of aggregate to total dry raw materials, and a highly-homogenous distribution of a non-absorptive and closed-cell lightweight aggregate such as glass microspheres or copolymer polymer beads or a combination thereof, and the steps of providing the composition or components. Lightweight concretes formed therefrom have low density, high strength-to-weight ratios, and high R-value. The concrete has strength similar to that ordinarily found in structural lightweight concrete but at a lower density, such as an oven-dried density as low as 40 lbs./cu.ft. Such strength-to-density ratios range approximately from above 30 cu.ft/sq.in. to above 110 cu.ft/sq.in., with a 28-day compressive strength ranging from about 3400 to 8000 psi.

A low-density, high-strength concrete composition that is lightweight and self-compacting or non-self-compacting, with a low weight-fraction of aggregate to total dry raw materials, and a highly-homogenous distribution of a non-absorptive and closed-cell lightweight aggregate such as glass microspheres or copolymer polymer beads or a combination thereof, and the steps of providing the composition or components. Lightweight concretes formed therefrom have low density, high strength-to-weight ratios, and high R-value. The concrete has strength similar to that ordinarily found in structural lightweight concrete but at a lower density, such as an oven-dried density as low as 40 lbs./cu.ft. Such strength-to-density ratios range approximately from above 30 cu.ft/sq.in. to above 110 cu.ft/sq.in., with a 28-day compressive strength ranging from about 3400 to 8000 psi.

A dry construction composition is easily wet-sprayable by means of a screw pump, thus forming, after hardening, a durably mechanically resistant insulating material (λ<0.1 W.Math.m−1.Math.K−1). The composition contains: —A— at least one binder, itself including: —A1— at least one main binder containing lime and/or at least one alumina source and/or at least one calcium sulfate source, preferably at least one alumina source, —A2— at least one water-retaining agent, and —A3— preferably at least one surfactant; and —B— at least one biosourced filler, preferably of plant origin. The ratio B/A (liters/kg) is between 2 and 9. The composition is intended to be mixed with water in a water/binder ratio —A— of no lower than 0.8. Also disclosed is a wet composition, the preparation thereof, to the binder —A— taken in isolation, and to a method of spraying the composition onto a horizontal or vertical substrate or by molding.

A dry construction composition is easily wet-sprayable by means of a screw pump, thus forming, after hardening, a durably mechanically resistant insulating material (λ<0.1 W.Math.m−1.Math.K−1). The composition contains: —A— at least one binder, itself including: —A1— at least one main binder containing lime and/or at least one alumina source and/or at least one calcium sulfate source, preferably at least one alumina source, —A2— at least one water-retaining agent, and —A3— preferably at least one surfactant; and —B— at least one biosourced filler, preferably of plant origin. The ratio B/A (liters/kg) is between 2 and 9. The composition is intended to be mixed with water in a water/binder ratio —A— of no lower than 0.8. Also disclosed is a wet composition, the preparation thereof, to the binder —A— taken in isolation, and to a method of spraying the composition onto a horizontal or vertical substrate or by molding.