Patents Examined by Nancy J. Stodda
  • Insulation of tunnel linings
    Patent number: 4432667
    Abstract: A tunnel or shaft lining is installed nondisruptively in a medium such as soil by longitudinally advancing an assembly (10) of tunnel lining sections (12-1 to 12-8) arranged in end-to-end relationship and having an inflatable torus (22- 1 to 22-7) interposed between adjacent sections. Worm-like advancement is effected by simultaneously inflating in sequence the tori 22-1, 22-4, 22-7 etc.; the tori 22-2, 22-5 etc. and the tori 22-3, 22-6 etc., and repeating the inflation procedure as necessary until sufficient advance has been achieved.
    Type: Grant
    Filed: June 10, 1980
    Date of Patent: February 21, 1984
    Assignee: Marcon International Limited
    Inventor: Michael A. Richardson