Tensioned & Untensioned Rod Extensometers
Rod extensometers are used to monitor small displacements of soil
or rock along the axis of a borehole.
A Single-Point Rod Extensometer consists of an anchor, a rod, and
a reference head. The anchor, with rod attached, is installed down
hole. The reference head is installed at the borehole collar. The rod
spans the distance from the anchor to the reference head. A change
in this distance indicates that ground movement has occurred. Mea-
surements are obtained at the reference head with a depth microme-
ter or an electronic sensor and are used to compute the magnitude,
rate, and acceleration of displacement. When the reference head or
the
anchor can be located with respect to a fixed reference datum,
absolute displacements can be determined.
A Multi-Point Rod Extensometer consists of up to six anchors and
rods and one reference head. Anchors are set near different strati-
graphic boundaries. Measurements are obtained at the reference
head with a depth micrometer or an electronic sensor. Multi-point
extensometer data can reveal the relative movement between
anchors and the distribution of displacement in addition to the
magnitude, rate, and acceleration of displacement.
Borehole Extensometers
6-13
Rembco Geotechnical Contractors specializes in
slope stabilization,
soil nail wall,
foundation repair
and support,
grouting,
shoring,
micropile
construction,
rock drilling, and we remediate
sinkholes. We use a
problem-solving approach in the geotechnical portions of buildings, bridges, water plants, sewage plants, tunnels,
installing caisson bottom, and roads. We are experienced in these applications:
micro piles,
sinkhole repair,
permeation and
pressure
grouting,
soil nails,
cement grouting,
chemical grouting,
micropiles,
compaction grouting, and
rock anchors.
Rembco techniques apply when adding new structures: especially
rock anchor,
microfine cement,
soil nailing, and
micropile
installations for foundation support. Our specialties are
soil nails,
rock anchor,
chemical and
compaction grouting,
mini piles,
sinkhole repair,
micropiles, and
soil nailing.
