For quick and accurate measurement of relative distances between pairs of reference points on the surfaces of structures including radial movements and convergence of tunnels, shafts, linings and caverns, deformation of excavations in underground caverns and displacements of retaining walls, cuttings, bridge piers, arches

The measurement of displacement takes place between pairs of reference studs or eyebolts grouted into shallow drill holes in the structure or excavation. The studs or eyebolts are permanently fixed to provide a precise fixing point at the surface of the structure. Demountable extension studs are available for fixing in locations where, for instance, additional shotcrete is applied to the surface to be monitored.

The tape extensometer unit comprises a stainless steel measuring tape with equally spaced precision punched holes. The fixed end of the tape is fitted to the tape winding reel integral with the lightweight body which has a connector identical to that on the free end of the tape. The body incorporates a tape tensioning device coupled to a digital LCD readout. A location pin is engaged into the appropriate tape hole and is secured with a retaining clip. To adjust the tape tension, a knurled collar is rotated until the white cursor lines on the face plate and internal spring anchor block are precisely aligned.

A reading is taken by noting the visible pin hole position on the tape at the instrument nose and adding the reading on the internal sliding scale and digital readout.

It is important to note that the measurements being taken are not absolute, but rather looking for a measurement relative to the previous measurement or movement over time.

Please request Manuals through info@itm-soil.com.au