Download Vibrating Wire Piezometer - Manual

Version 1.4 May 09
(Continued from page 20)
13. Pull the casing back another 500mm (or as
project specification requires) and add a
Bentonite seal of specified thickness. This
should comprise pure Bentonite pellets / balls
as described above for the base plug. Continue
to pull the casing a little at a time whilst adding
the Bentonite pellets. Once the borehole is
sealed to the specified thickness, check
piezometer readings again.
( In a 100mm diameter borehole the 5kg of
Geosense Mikolit® Bentonite pellets will produce
a seal approximately 500mm long )
14. Fill the remaining void with Grout as shown in
the grouting procedure ( See Section 5.6 ).
15. The piezometer installation is now complete but
the initial, in-situ piezometer readings have yet
to be recorded. Since the piezometric balance
may have been disturbed by the installation
operations, a series of piezometer readings may
have to be recorded so as to determine when
the piezometric balance has re-established.
Only then can a true set of in-situ pore pressure
readings be recorded.
16. Terminate the installation as specified. It is
important to terminate the cable above ground
level in a waterproof enclosure or with a
waterproof connector. Protect the installation
from construction traffic and mark its location
with a stake.
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