Details• Sisgeo Borehole Rod Extensometers are installed in borehole to monitor displacements at various depths using rods of different material 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 at factory and shipped ready for installation.
• The complete assembly is inserted into the borehole and then grouted, fixing the anchors to the rock or soil but allowing free movement of each rod within its sleeve.
• Relative movements between the anchors and the reference head are measured manually with caliper or linear transducers, assembled on the reference head for remote monitoring.