Mounted in vertical or horizontal boreholes to measure settlement or deformation axially along the borehole/measuring channel.
The extensometer consists of a reference head that is attached to the borehole opening and one or more anchors that are installed at different depths and cast in place.
The anchors are connected to the head via rods, which can move in protective tubes. Rods and tubes are available in fiberglass or stainless steel.
Changes in distance to the anchors are read either manually with a micrometer, electrical reading instrument - or using a data logger.
Precision gauge with steel measuring tape for checking the distance between fixed anchors. Typical applications are in tunnels and caverns, as well as control of crack development in rock, structures, rock blocks, etc.
2023 Geonor
