Patent ID: 8906156

Claim:
A method for forming a cement or concrete composition, comprising: combining a cementitious composition wherein the cementitious composition comprises a metastable component selected from the group consisting of vaterite, amorphous calcium carbonate, and combination thereof, with a reinforcing material wherein the reinforcing material is selected from the group consisting of aluminum, glass fiber, carbon fiber, ceramics, polymer, grass, grass product, wood product, fiber-reinforced plastic, epoxy coated rebar, titanium cladding treated rebar, chrome plated/coated rebar, nickel plated/coated rebar, cobalt-chromium coated rebar, polycarbonate reinforcing members, polycarbonate fiber, poly(vinyl chloride) (PVC) reinforcing members, PVC fiber, polypropylene, cellulose, polyvinyl alcohol, bamboo, and combination thereof, to form a cement or concrete composition; and contacting the cement composition or the concrete composition with water to cause dissolution-reprecipitation of vaterite to aragonite wherein the composition after contact with water has a wet paste pH of less than 12, and setting and hardening wherein aragonitic crystals are formed on the reinforced material.