Rod extensometers are installed in boreholes in order to monitor displacements at various depth using rods of different materials and lengths.

A pre-set length of measuring rod is inserted into a nylon tube to avoid soil friction and its tip is fixed to a steel groutable anchor. Preassembled fibre glass rods are coiled when manufactured and shipped ready for installation.

Stainless steel and invar rods are supplied in bars of 2 meters length; they need to be mounted on-site.

The complete rod extensometer assembly is grouted through a dedicated tube, fixing the anchors to the rock or soil but, at the same time, allowing free movement of each rod within its sleeve..

Technical specifications

0D222AC00A0    Stainless steel or invar rods, DTE˂100mm
0D222AC00B0    Stainless steel or invar rods, DTE˃100mm
0D222FG00A0    Fibre glass rods, DTE˂100mm
0D222FG00B0    Fibre glass rofs, DTE˃100mm
Number of bases    1 (single), from 2 to 7 (multiple)
Multiple head top tube    0D 120mm
Extensometer rods    FG fibre glass continuous
AC stainless steel, 2m sections
IN invar, 2m sections
Protective sleeve    Nylon 11 (rilsan), 0D 12mm
Groutable anchor    FG: rebar 16mm 0D, 400 mm long
AC/IN rebar 22m 0D, 400 mm long
System components    
0D221BMFG00    Fibre glass rod, D 7mm
0D221BMAC00    Stainless steel rod, 0D 8mm
0D221BMIN00    Invar rod, 0D 8mm
0D222TOP200    Protective cap, DTE: 10,25, 50mm
0D222TOP320    Protective cap, DTE: 100,150,200mm
0D222KT0P01    Single base cap kit
0D222K7AC00    Installation kit for AC/N rods
0D222K6FG00    Installation kit for FG rods
Digital gauge (Product code 0DIGD020000)    
Measuring range    From 0 to 200mm
Resolution     0.01mmЙ