Abstract: The invention relates to a relates to an acid activated mixture comprising: an acid activated magnesium-iron solid solution silicate filler; cementitious material; and carbon dioxide (CO2); wherein the magnesium-iron solid solution silicate filler has at most 7% free water, and wherein the magnesium-iron solid solution silicate filler is between 4% and 55% by weight of cementitious material. The invention further relates to a method for producing an acid activated cement slurry comprising the steps: making a slurry comprising a non-acid activated or acid activated magnesium-iron solid solution silicate filler, water, and cementitious material; adding carbon dioxide (CO2) to the slurry; and optionally adding an acid to the slurry; wherein the magnesium-iron solid solution silicate filler is between 4% and 55% by weight of cementitious material.

Abstract: The invention relates to a process for preparing an alkali activated binder mixture comprising mixing: (i) 50 to 100% by weight of ultramafic rock, based on the weight of the binder mixture, (ii) 0 to 60% by weight of aluminosilicate precursor, based on the weight of the binder mixture, (iii) an alkali activator, wherein the ultramafic rock and aluminosilicate precursor are present in an amount of less than or equal to 95% by weight of the binder mixture, wherein the alkali activator dosage (R) is between 3 and 14, where R is given by the mass ratio: R=Mass of Na2O or K2O in the alkali activator×100 Mass of the binder mixture, and wherein the activator modulus (M) is between 0 and 3, where M is a mass ratio given by: M=SiO2 or SiO2 Na2O K2O.

Abstract: A cementitious mixture to make structures with reduction of gas permeability was disclosed. The mixture includes, cementitious materials, and one or more divalent magnesium-iron silicate that in neutral or basic aqueous solutions have the capacity to be a latent hydraulic binder comprising 2% to 99% of divalent magnesium-iron silicate by weight of total hydraulic solid materials. This can be used to produce a cementitious structure for preventing gas transfer between a first region and a second region. A cement slurry was also disclosed.

Abstract: A cementitious mixture to make structures with reduction of gas permeability was disclosed. The mixture includes, cementitious materials, and one or more divalent magnesium-iron silicate that in neutral or basic aqueous solutions have the capacity to be a latent hydraulic binder comprising 2% to 99% of divalent magnesium-iron silicate by weight of total hydraulic solid materials. This can be used to produce a cementitious structure for preventing gas transfer between a first region and a second region. A cement slurry was also disclosed.

Abstract: The invention pertains to performing bonding strength testing between a test material and a container. A sample preparation device to make a test sample was disclosed. This device included a container with an insert on each end. The inserts have a portion that protrudes into the container. When test material is added to the sample preparation device, a groove was formed in test sample. These grooves reduce the amount of boundary effects that are present during testing. A system and method for performing bond strength testing was also disclosed. In this system, a test sample was formed using the sample preparation device. This is placed upon a support and a half-spherical force applier is placed on top of the test sample. A press is used to apply force to the force applier and indirectly to the test sample.

Abstract: A composition of a cement additive material to improve durability of cementitious structures, was disclosed. The cement additive composition includes an admixture of one or more of divalent magnesium metal silicates with capacity to act as a latent hydraulic binder in said composition activated by a hydration process under aqueous conditions, and in particular the divalent metal silicate is magnesium-dominated silicate, preferably comprising mineral groups of olivines, orthopyroxenes, amphiboles, and serpentines or mixtures thereof. The composition also includes chloride ions or brine.

Abstract: A composition of a cement additive material to improve durability of cementitious structures, was disclosed. The cement additive composition includes an admixture of one or more of divalent magnesium metal silicates with capacity to act as a latent hydraulic binder in said composition activated by a hydration process under aqueous conditions, and in particular the divalent metal silicate is magnesium-dominated silicate, preferably comprising mineral groups of olivines, orthopyroxenes, amphiboles, talc and serpentines or mixtures thereof. The composition also includes chloride ions or brine. Applications of the compositions are also disclosed, in particular to utilize a property of hydration as a major trigger for the latent hydraulic reaction of magnesium silicates, particularly for said olivines, when exposed to water and brines, in order to obtain a cementitious material becoming self healing.