Borehole Extensometers

Brochure
Manual

DESCRIPTION

Stability and movement behavior of soil and rock masses can be determined by the use of borehole extensometers. A typical rod extensometer consists of a reference head, usually installed at the collar of a drill hole, and one or more in-hole anchors, each of which is fixed in place at a known depth in the borehole. As the soil or rock deforms, the distances between adjacent in-hole anchors change, as do the distances between the individual in-hole anchors and the reference head. This allows an accurate determination of distribution, magnitude, rate and acceleration of deformation in the rock or soil mass intersected by the drill hole.

APPLICATIONS

  • Monitoring deformation around underground excavations.
  • Movement behind the face of excavated slopes.
  • Consolidation settlement in soils.
  • Bottom heave in open cut excavations.
  • Strain in concrete structures.
  • Subsidence over mines, tunnels, etc.
  • Pile load tests.
  • Monitoring of mine pillar deformation.
  • Deformation of foundations in and under buildings.
  • Roof and wall stability in mines and underground workings.

QUICK SPECS

  • Accurate and reliable.
  • Easily adapted to remote readout.
  • Anchor lengths can be varied in the field.
    * for Rigid Rod Extensometers only.
  • Rugged, easy to install, and simple to operate.

VIEW ILLUSTRATIONS ON HOW THIS IS USED FOR: