GROUNDWATER
it appears desirable to evaluate grout
consistency quantitatively, using the
Marsh Funnel for instance. Marsh
Funnel tests can easily be conducted
in the field. Further work is needed on
the relationship between grout stability
and permeability, and Marsh Funnel
viscosity.
Conclusion
This paper investigated the field
responses of fully-grouted piezom-
eters sealed within a Champlain clay
deposit using two grout recipes. The
study showed that grout hydraulic
conductivity and stability are key
parameters for a successful fully-
grouted installation. Baseline pore
pressure monitoring demonstrated that
a grout with a ratio of around 1100
between grout and surrounding clay
permeability resulted in a hydraulic
short-circuit between the piezometer
and the upper aquifer. However, the
piezometer that was sealed with a
grout with a hydraulic conductivity
ratio of less than 10 gave a smooth and
dampened response as expected for
an intact clay deposit. Our field and
laboratory tests also indicate that the
and needs to be considered for fully-
grouted installations.
Acknowledgment
The authors would like to acknowl-
edge the funding of NSERC and GKM
Consultants for this project.
References
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Vahid Marefat
Laboratory for Geotechnical and
Geoenvironmental Engineering
(LG2), École de technologie
supérieure, 1100 Notre-Dame
Ouest, Montreal, QC, H3C 1K3,
Canada,
T; 1-438-931-9797
François Duhaime
Laboratory for Geotechnical and
Geoenvironmental Engineering
(LG2), École de technologie
supérieure, 1100 Notre-Dame
Ouest, Montreal, QC, H3C 1K3,
Canada
Robert P. Chapuis
Department CGM, École Polytech-
nique de Montréal, P.O. Box 6079,
Station CV, Montreal, QC, H3C
3A7, Canada
Vincent Le Borgne
GKM Consultants, 2141 Nobel,
