Durable concrete and method for producing the same
A concrete mix for producing freeze-thaw durable concrete having enhanced strength properties, like compressive strength, abrasion resistance, impact strength, toughness, is disclosed. The novel concrete mix contains deformable solid elements in place of 4-8% entrained air for good durability of concrete under freeze-thaw cycles.
1. A hardened concrete resistant to cracking in a freeze-thaw environment, comprising the following components:
cement;
aggregates;
optionally admixtures; and
deformable spaces containing physical or chemical remnants of inorganic disintegrated solid elements,
wherein the total volume of said deformable spaces is less than 2%, and the maximum dimension of said deformable spaces is less than about 300 micrometers, and the distance between the deformable spaces is no greater than about 200 micrometers, so as to prevent a pressure build-up in capillary pores of cement gel exceeding 1000 psi upon freezing of water within the capillary pores, said hardened concrete having a density above about 1.5 g/cm 3 .
2. The hardened concrete of claim 1 , wherein said deformable spaces contain physical or chemical remnants of inorganic, hollow, spherical, deformable solid elements.
3. The hardened concrete of claim 2 , wherein said inorganic deformable solid elements are made of materials selected from the group of glass, ceramic and silica and combinations thereof.
4. The hardened concrete of claim 2 , wherein said spheres have a crush strength of <1000 psi.
5. The hardened concrete of claim 3 , wherein said inorganic deformable solid elements are cenospheres.
6. The hardened concrete of claim 3 , wherein said inorganic deformable solid elements are deformed by chemical disintegration over time.
7. The hardened concrete of claim 6 , wherein said inorganic deformable solid elements are glass spheres.
8. The hardened concrete of claim 1 , which has a density of above about 2 g/cm 3 .
9. The hardened concrete of claim 1 , which has a density of above about 2.5 g/cm 3 .
10. The hardened concrete of claim 1 , which has a density from about 2 g/cm 3 to about 2.5 g/cm 3 .
11. The hardened concrete of claim 1 , wherein the total volume of said deformable spaces is less than about 1%.
12. The hardened concrete of claim 1 , wherein the total volume of said deformable spaces is less than or equal to about 0.6%.