Methods of reducing hydroxyl ions in concrete pore solutions
US7608143B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Jun 21, 2005 |
| Grant date | Oct 27, 2009 |
| Priority date | — |
| Expiry date | Jul 22, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B2111/2023
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Methods of reducing hydroxyl ions in concrete pore solutions are provided. Such methods are useful in providing resistance to gels which form in concrete due to the alkali-silica (ASR) reaction. The methods comprise, in one aspect, adding a salt, in aqueous or solid form, to the concrete, the salt having a cation higher in valence than the anion. In other aspects, the methods of the present invention comprise adding an acidic phosphate or a silicon-containing alkoxide to the concrete. All of the above methods are useful in reducing hydroxyl ions in concrete. Such methods can be used to resist ASR in fresh concrete, in concrete that is setting, or in hardened concrete. Methods are also provided for mitigating ASR while simultaneously healing cracks in concrete or bonding new concrete to existing concrete. The methods involve reacting an Si-containing alkoxide with a source of reactive calcium to produce calcium silicate hydrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.