The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 13, 2023
Filed:
Jan. 31, 2022
Pq, Llc, Malvern, PA (US);
Michael McDonald, Toronto, CA;
Kelly Paul Short, O'Fallon, MO (US);
Kenneth A. Berg, North Wales, PA (US);
Flavio Ernesto Ribeiro, Plainfield, IL (US);
Jim Moran, Philadelphia, PA (US);
Peter Marinescu, Toronto, CA;
Daoping Guo, Ontario, CA;
PQ, LLC, Malvern, PA (US);
Abstract
A method and composition are provided for backfilling the annular gap created as a tunnel boring machine advances through the ground. The fill material is comprised of two components that are combined and mixed together just prior to entering the annular gap. The first component is non-cement slurry consisting of a fluidized bed combustion ash such as coal ash. The second component consists of an alkali silicate such as sodium silicate. Additionally, ordinary Portland cement and/or metakaolin can be added to the grout composition.