Mobile train for backfilling tunnel liners with cement grout
OwnerPatrick J. Stephensinventor
Life of this patent
Estimating the term…
Abstract
A mobile train for mixing foamed cement grout within a tunnel and injecting the grout into the annular cavity between the tunnel bore and liner. Cement slurry is suppled to the train through a conduit from a remote mixing plant, and finished foam is formed by a foam generator on the train and mixed with the cement slurry to form the fooamed cement grout. The train is movable longitudinally through the tunnel so that the liner can be grouted in segments while at the same time avoiding the need to pump the foamed cement grout over excessively long distance. The train is made up of several wheeled cars which are pulled through the tunnel by a tractor.
Claims31
A machine for grouting an annular cavity formed intermediate an elongate external bore and a tubular internal member disposed in said bore, said machine comprising:
- vehicle means configured for longitudinal movement in said tubular internal member;
- means for supplying cement slurry to said vehicle means from a remote site;
- foam generating means mounted on said vehicle means for forming finished foam;
- mixing means mounted on said vehicle means for mixing said finished foam with said cement slurry to form foamed cement grout;
- and
- means for injecting said foamed cement grout from said vehicle means into said cavity intermediate said internal tubular member and said external bore;
- whereby said vehicle means is movable longitudinally in said internal tubular member so as to permit said foamed cement to be formed and injected into said cavity at longitudinally spaced apart locations along said internal member.
A machine for grouting an annular cavity formed intermediate a tunnel bore and a tunnel liner disposed in said tunnel bore, said machine comprising:
- a vehicle configured for longitudinal movement in said tunnel liner;
- a supply conduit for conveying cement slurry to said vehicle from a cement mixing plant positioned outside of said tunnel;
- a container mounted on said vehicle for carrying a supply of liquid foam concentrate;
- a foam generator mounted on said vehicle for mixing said liquid foam concentrate with water and air to form finished foam;
- mixing means mounted on said vehicle for mixing said cement slurry which is conveyed to said vehicle with said finished foam to form foamed cement grout;
- a discharge conduit for conveying said foamed cement grout from said vehicle to an injection point into said cavity intermediate said tunnel bore and said tunnel liner:
- and
- a pump mounted on said vehicle for pumping said foamed cement grout through said flexible discharge conduit and into said cavity;
- whereby said vehicle is movable longitudinally through said tunnel liner to spaced-apart locations relatively near various said injection points and said supply conduit permits said cement slurry to be conveyed to said vehicle over relatively long distances from said mixing plant at said remote location and said discharge conduit permits said grout to be conveyed from said vehicle over relatively short distances to said injection points relatively near said locations of said vehicle.
A method for grouting an annular cavity intermediate a tunnel bore and a tunnel liner disposed in said tunnel bore, said method comprising:
- positioning a vehicle for longitudinal movement in said tunnel liner;
- supplying cement slurry to said vehicle through a conduit from a cement mixing plant positioned outside of said tunnel liner;
- mixing liquid foam concentrate on said vehicle with air and water to form finished foam;
- mixing said cement slurry with said finished foam on said vehicle to form foamed cement grout;
- and
- pumping said foamed cement grout from said vehicle into said cavity intermediate said tunnel bore and liner.
Dependencies are inferred from the claim text.