Method and apparatus for continuous production of quick-setting foamed cement grout with selectively adjustable proportions
US5803665A · kind A · utility
Inventor
Key dates
| Filing date | May 17, 1996 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | May 17, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/91
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method and apparatus for continuous production of a quick-setting foamed cement grout, in which the individual constituents of the grout are proportionally adjustable. Finished foam and cement slurry are mixed at metered rates to form a foamed cement grout which is pumped to a wye connection proximate a remote injection site. Sodium silicate solution is added at the wye connection at a metered rate, using a second metering pump. The sodium silicate solution mixes with the foamed cement grout to greatly accelerate the setting time thereof, and compressed air may also be added to accelerate the passage of the material through the injection hose and nozzle. The quick-setting material is particularly suited for use with a tunnel boring machine (TBM), to grout the annular cavity between the tunnel bore and the segmented liner which is installed therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.