42
Geotechnical News June 2011
THE GROUTLINE
That particular, and memorable,
technical session in New Orleans in
2003 continued at a rapid pace for
much longer than the organizers had
intended, reflecting much credit in both
protagonists. The opinion of the author
is as follows:
• Hydraulic fracturing (and, for
that matter, fracture dilation or
surface displacement) can read-
ily and quickly be recognized by
competent, experienced personnel
using modern real-time monitor-
ing equipment and procedures.
Injection pressures can then be re-
duced, and injection can be slowed
or stopped as appropriate before
excessive volumes of grout are in-
jected.
• On the second point, although ad-
justing the rheology of the grout
rather than halting injection to limit
grout travel after some prescribed
maximum volume has been in-
jected, is favorable application of
conservative curtain closure crite-
ria and procedures would, in most
if not all cases, provide additional
opportunities to complete the fill-
ing of wider open joints.
In retrospect, had the esteemed
Dr. Lombardi strongly and widely
promoted his Theory in the U.S. during
the time of the U.S. grouting industry
“fin de siècle” (i.e., the late 1980’s),
then it is highly probable that the entire
North American continent, in addition
to South America, would have had a
different grouting direction. Instead,
this flare from Europe has fallen
between the two stools of the U.S.
grouting practice, one anchored in the
early 1920’s, the other springing from
the revolution of the mid-1990’s. In
summary, GIN Theory most probably
has worked well and was an excellent
option in the grouting interregnum in
developing countries during the latter
decades of the 20th Century. However,
the approaches developed in North
America over the last 15 years have
been verified to give truly exceptional,
compliant and consistent results, using
means and methods which are site-
specific. In effect, there was a "GIN
window" in the U.S. between 1985 and
1995 during which GIN Theory could
have become predominant,but did not,
and to now to promote it in the U.S. is
regressive.
Conclusion
Current U.S. dam curtain grouting
practice for seepage control has
evolved during the last 15 years or so
to a level that it can assure a responsive
and effective solution to any project-
specific challenge, be it a remedial
application, or a new dam curtain. For
the benefit of the industry, it is essential
that two tasks are implemented. The first
is to eradicate the “old ways”: this in
itself is a matter of technical education,
although the quality, intensity and
consistency of the education need
to be pursued with constancy and
vigor. The second is to be on guard
against regression, which is typified
by adoption of concepts which were
popular decades ago in other countries,
but for different reasons, did not arrive
in the U.S.
For the first time in our dam grout-
ing history, North America has a cur-
rent approach and a track record which
is without equal in the world. This is
partly due to the severity of the chal-
lenges we face, but also is a result of
a typically uniquely North American
mélange of concepts and resources.
The recent record speaks for itself with
excellent results having been achieved
on remedial grouting projects at many
USACE DSAC-1 projects in particular.
While we should and will remain re-
ceptive to new developments, we must
not allow the industry to give up the
successes of the last decade.
References
Albritton, J.A. (1982). “Cement Grout-
ing Practices U.S. Army Corps of
Engineers.” American Society of
Civil Engineers, Geotechnical En-
gineering Specialty Conference on
Grouting, New Orleans, February
10-12, pp. 264-278.
Bruce, D.A., J.P. Davis. (2005). “Drill-
ing through Embankments: The
State of Practice,” USSD 2005
Conference, Salt Lake City, UT,
June 6-10, 12 p.
Bruce, D.A. and T.L. Dreese. (2010).
“Specifications for Rock Mass
Grouting,” ASDSO Dam Safety
Conference, September 19-23, Se-
attle, WA, 12 p.
DePaoli, B., B. Bosco, R. Granata,
and D.A. Bruce. (1992). “Funda-
mental Observations on Cement
Based Grouts (1) : Traditional Ma-
terials.” Proc. ASCE Conference,
“Grouting, Soil Improvement and
Geosynthetics,” New Orleans, LA,
February 25-28, 2 Volumes, pp.
474-485.
Dreese, T.L., D.B. Wilson, D.M. Heen-
an, and J. Cockburn. (2003). “State
of the Art in Computer Monitoring
and Analysis of Grouting.” Grout-
ing and Ground Treatment, Pro-
ceedings of the Third International
Conference, Geotechnical Special
Publication No. 120, Ed. L.F. John-
sen, D.A. Bruce, and M.J. Byle,
American Society of Civil Engi-
neers, pp. 1440-1453.
Ewert, F.K. (2003). “Discussion of
Rock Type Related Criteria for
Curtain Grouting.” Proceedings of
the Third International Conference
on Grouting and Ground Improve-
ment, ASCE Special Publication
No. 120.
Franklin, J.A. and M.B. Dusseault.
(1989). “Rock Engineering.” Mc-
Graw-Hill, New York, March, 610
p.
Foundation for Dams. (1974). ASCE
Proceedings, Engineering Founda-
tion Conference, Asilomar Confer-
ence Gorunds, Pacific Grove, CA,
March 17-21, 472 p.
Glossop, R. (1961). “The Invention and
Development of Injection Process-
es, Part 2, 1850–1960.” Géotech-
nique, 11, 4, December, 255–279.
Houlsby, A.C. (1976). “Routine In-
terpretation of the Lugeon Water-
Test.” Quarterly Journal of Engi-
neering Geology, 9(4), 303-313.
Houlsby, A.C. (1990). “Construction
and Design of Cement Grouting.”
John Wiley and Sons, 442 p.
Littlejohn, G.S. (2003). “The Develop-
ment of Practice in Permeation and
Compensation Grouting: A Histori-
cal Review (1802 – 2002) Part 1
Permeation Grouting.” Grouting
and Ground Treatment, Proceed-
ings of the Third International Con-
