Patents by Inventor Gavin Stuart Littlejohn

Gavin Stuart Littlejohn has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20030015038
    Abstract: A ground anchorage testing arrangement having an impulse imparting apparatus connectable to a ground anchorage tendon (20) or element thereof to be tested, the impulse imparting apparatus comprising an attachment means (22) for attachment to the ground anchorage tendon (20), a movable mass (31), a guide (28, 34) for guiding movement of the mass in the direction substantially aligned with the axis 0 of the ground anchorage to be tested and a drive means for imparting a driving force to move the mass in said direction (not shown). A method of assessing the integrity of ground anchorages, the method comprising the steps of (a) imparting a load impulse to a ground anchorage tendon to be tested, (b) monitoring the vibrational response signal of the anchorage to the imparted load impulse, (c) conditioning the vibrational response signal and (d) applying the conditioned vibrational response signal to an artificial neural network.
    Type: Application
    Filed: April 12, 2002
    Publication date: January 23, 2003
    Inventors: Albert Alexander Rodger, Gavin Stuart Littlejohn, Richard David Neilson, James Penman
  • Patent number: 6422079
    Abstract: A ground anchorage testing arrangement having an impulse imparting apparatus connectable to a ground anchorage tendon (20) or element thereof to be tested, the impulse imparting apparatus comprising an attachment means (22) for attachment to the ground anchorage tendon (20), a movable mass (31), a guide (28, 34) for guiding movement of the mass in the direction substantially aligned with the axis 0 of the ground anchorage to be tested and a drive means for imparting a driving force to move the mass in said direction (not shown). A method of assessing the integrity of ground anchorages, the method comprising the steps of (a) imparting a load impulse to a ground anchorage tendon to be tested, (b) monitoring the vibrational response signal of the anchorage to the imparted load impulse, (c) conditioning the vibrational response signal and (d) applying the conditioned vibrational response signal to an artificial neural network.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: July 23, 2002
    Assignees: Aberdeen University, University of Bradford
    Inventors: Albert Alexander Rodger, Gavin Stuart Littlejohn, Richard David Neilson, James Penman
  • Patent number: 5850884
    Abstract: A moling apparatus comprises a housing having a head for penetrating ground, an anvil in the housing connected to the head, and a hammer in the housing and spaced therefrom by a spring. A vibrator unit is spaced from the hammer and arranged to transfer vibration to the housing and the hammer. In a first mode of the apparatus, vibration transmitted to the housing causes fluidization of the surrounding ground to allow progressive penetration of the apparatus. In a second mode, the braking effect of the ground on the head causes the hammer to move against the spring and impact the anvil thereby driving the head through the ground, the apparatus being operable at or between each mode.
    Type: Grant
    Filed: January 27, 1997
    Date of Patent: December 22, 1998
    Assignees: Aberdeen University, The University of Bradford
    Inventors: Albert Alexander Rodger, Gavin Stuart Littlejohn
  • Patent number: 5798981
    Abstract: A method and apparatus for monitoring the condition of a ground anchorage including a tendon arranged in a bore in a group formation at a site is characterized by detecting the vibrational response signature of the anchorage to an impulse load. The vibrational response signature to the impulse is recorded and compared with a reference signature from which any changes in the integrity of the anchorage can be determined.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: August 25, 1998
    Assignees: Aberdeen University, The University of Bradford
    Inventors: Gavin Stuart Littlejohn, Albert Alexander Rodger