A process to enhance the pozzolanic activity of a natural inactive sedimentary pozzolan and the pozzolanic material formed by the process are described. The process comprises the steps of finely dividing the pozzolan to a Blaine fineness of at least 8,000 cm.sup.2/g for increasing the surface area of the finely ground pozzolan and exposing a great amount of the number of silicon and aluminum atoms available to react with lime in a pore solution.

A concrete composition that includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) a coarse aggregate, and (iv) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate. A cured concrete made from the concrete composition is also disclosed with advantageous compressive strength properties.

A concrete composition that includes (i) a treated palm oil fuel ash, wherein the treated palm oil fuel ash is the only binder present, (ii) a fine aggregate, (iii) a coarse aggregate, and (iv) an alkali activator containing an aqueous solution of sodium hydroxide and sodium silicate. A cured concrete made from the concrete composition is also disclosed with advantageous compressive strength properties.

A cementitious composition of one embodiment, according to the present teaching, includes, but is not limited to, a Portland cement, and at least one other cement from a group comprising, but not limited to, calcium sulfoaluminate cement, a calcium aluminosilicate cement, and calcium aluminate, wherein the Portland cement has a content of at least 20 percent based on the total weight of the non-Portland hydratable cement powder, wherein the cementitious composition bonds to asphalt.

A cementitious composition of one embodiment, according to the present teaching, includes, but is not limited to, a Portland cement, and at least one other cement from a group comprising, but not limited to, calcium sulfoaluminate cement, a calcium aluminosilicate cement, and calcium aluminate, wherein the Portland cement has a content of at least 20 percent based on the total weight of the non-Portland hydratable cement powder, wherein the cementitious composition bonds to asphalt.

Methods of preparing a cementitious structure for carbon dioxide (CO.sub.2) sequestration are provided. The cementitious structure may be a cast in a mold. First, a cementitious composite material comprising binder and water is conditioned, for example, in a mold by exposing the cementitious composite material to ≥about 50% to ≤about 80% relative humidity for ≥about 3 hours to ≤about 24 hours. The cementitious composite material is then dried to remove ≥about 10% by weight of initial water in the cementitious composite material. The cementitious structure formed is capable of a carbon dioxide uptake level of greater than or equal to about 6% by weight binder. The cementitious structure has a tensile strain capacity of ≥about 1% and a uniaxial tensile strength of ≥about 1 MPa. The method may also include carbonating the cementitious structure, following by an optional further hydration process.

Methods of preparing a cementitious structure for carbon dioxide (CO.sub.2) sequestration are provided. The cementitious structure may be a cast in a mold. First, a cementitious composite material comprising binder and water is conditioned, for example, in a mold by exposing the cementitious composite material to ≥about 50% to ≤about 80% relative humidity for ≥about 3 hours to ≤about 24 hours. The cementitious composite material is then dried to remove ≥about 10% by weight of initial water in the cementitious composite material. The cementitious structure formed is capable of a carbon dioxide uptake level of greater than or equal to about 6% by weight binder. The cementitious structure has a tensile strain capacity of ≥about 1% and a uniaxial tensile strength of ≥about 1 MPa. The method may also include carbonating the cementitious structure, following by an optional further hydration process.

The present invention relates to an additive for hydraulically setting compositions comprising a colloidally disperse preparation comprising at least one salt of a polyvalent metal cation with at least one organic phosphonate and/or phosphate compound as anion and at least one polymeric dispersant comprising anionic and/or anionogenic groups and polyether side chains. The additive is especially suitable as slump retainer and for improving early strength.

Concrete that exhibits increased flexibility (i.e., low modulus of elasticity) and high compressive strength is described. High aspect ratio structures as may be formed of the concrete are described. Structures formed of the concrete can have the same high compressive strength as similar structures formed from a more conventional concrete but can be significantly more flexible, which can allow for better load distribution in the structure and associated assembly. The concrete includes a weathered granite as coarse aggregate. The materials can be particularly beneficial in forming concrete components of a rail infrastructure, such as railroad ties and slabs.

A system and method of remediating an industrial, tailing, or fracking soil mass comprising the steps of analyzing a sample of at least one of the industrial, tailing, and fracking soil mass; wetting a predetermined volume of the industrial, tailing, or fracking soil mass with water to a predetermined minimum percentage of moisture content; spreading at least one of an inorganic polymer and stabilizing additive to the predetermined volume of industrial, tailing, or fracking soil mass; compressing the predetermined of industrial, tailing, or fracking soil mass under a predetermined load; spreading or spraying a polymerizing top sealer onto the predetermined of industrial, tailing, or fracking soil mass at a predetermined rate based upon a target soil mass and toxic content; and compressing or vibrating said treated and sealed predetermined of industrial, tailing, or fracking soil mass for compaction at a predetermined load.