The basic principles of the operation of a gas laser are outlined. The main uses of lasers are in pipe laying, tunnelling, site elevation control, plumbing and machine control. Pipe laying lasers are waterproof, robust and have a range of up to 150 M. Examples are given of their use in dealing with grades, elevation and line. Good accuracy in setting up can result in a fifteen percent saving in bed material. Less shoring is needed and it is estimated that the use of a laser makes the job easier, quicker and more accurate saving about 10 percent of the overall cost. Methods of minimising errors caused by refraction are discussed. Lasers for tunnelling control usually have a range of up to 500 M. A constant check is carried out on the tunnel progress. The beam can be used to check the squareness by the use of a prism turning it through 90 degrees. Dust and refraction can affect the beam. A rotating prism is used to give a level plane of light in site elevation uses. The beam is detected on special staff targets. The beam can be used on the actual job to control the level of strip, sub-base screeds and finished floors. It can also be detected by sensors fitted to earth-movers and level information fed to the operator. Most surface level lasers have an accuracy of plus or minus 0.01 percent. (TRRL)

  • Availability:
  • Corporate Authors:

    Embankment Press Limited

    Building 59, GEC Estate, East Lane
    Wembley, Middlesex HA9 7TQ,   England 
  • Authors:
    • CLARKE, J
  • Publication Date: 1980-4

Media Info

  • Features: Figures; Photos;
  • Pagination: p. 6
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00322216
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: May 21 1981 12:00AM