Geotechnical News • June 2012
33
THE GROUT LINE
8010, Austria;
,
Li Yan
, P.Eng., Engineering Team Lead, BC Hydro, 6911 Southpoint Drive,
Edmonds A02, Burnaby, B.C. V3N 4X8 Canada;
,
Stuart Littlejohn
, Emeritus Professor,
University of Bradford; Almsford House, Fulwith Mill Lane, Harrogate North, Yorkshire HG2 8HJ, United
Kingdom;
David Loyd
, Resident Engineer, U.S. Army Corps of Engineers, Resi-
dent Engineer’s Office, 310 Lancaster Rd., Lancaster, TN, 38569 US;
,
Ross T.
McGillivray
, P.E., Ardaman and Associates; 3925 Coconut Palm Drive, Suite 115, Tampa, FL, 33616 US;
David B. Paul
, Lead Civil Engineer, Risk Management Center, Corps of Engi-
neers; 13952 Denver West Parkway, Suite 200, Golden, CO, 80401 US;
David Siu
, P.Eng., Engineering Team Lead, BC Hydro, 6911 Southpoint Drive, Edmonds A02, Burnaby, BC.,
V3N 4X8, Canada;
,
Nate Snorteland
, P.E., Director, Risk Management Center,
Corps of Engineers; 13952 Denver West Parkway, Suite 200, Golden, CO, 80401 US;
Pat Taylor
, P.E., Mesa Associates, Inc., 1101 Market, EB A0C, Chattanooga, TN, 37402 US;
Walter Vanderpool
, P.E., Terracon Consultants; 750 Pilot Road, Suite F, Las Vegas,
NV, 89119 US;
Saman Vazinkhoo
, P.Eng., BC Hydro; 6911 Southpoint
Drive, Burnaby, B.C. V3N 4X8, Canada;
,
Kurt Von Fay
, P.E., U.S. Bureau
of Reclamation, MERL; P.O. Box25007/CodeD- 8180, Denver, CO 80225 US;
,
Robert
Waddell
, URS Corporation, 8181 East Tufts Avenue, Denver, CO 80237 US;
,
Tim
Wehling
, P.E., California Department of Water Resources; P.O. Box 942836, 1416 9th Street, Sacramento,
CA 95814 US;
,
Peter Yen
, Bechtel Corporation; 50 Beale Street, San Francisco, CA,
94105 US;
,
Michael Zoccola
, P.E., Chief, Civil Design Branch, Nashville District, Corps
of Engineers; 801 Broadway, Room 670/A-520, Nashville, TN 37203 US;
Background
A heated discussion occurred during
a question period at the 4
th
Inter-
national Conference on Grouting
and Deep Mixing (ICOG) in New
Orleans. The author (Ref. 1) had
summarized the investigation and
design of a grouting program to arrest
settlement of a nearly 100 year old
Amtrak bridge pier, located in deep
water, and crossing the mouth of the
Thames River in Connecticut. While
installing piles for a bridge retrofit,
one end of the pier supporting the lift
span began to settle, threatening a
disruption in continued rail service.
Initiation of rapid corrective action
was imperative, but little was known
about either the foundation, structure,
or the soils. An exploratory bor-
ing program and instrumentation of
the pier were immediately initiated,
as were consideration of remedial
approaches. Although little was known
about the underlying foundation,
it was concluded that some sort of
pressure grouting would be required.
Early on the team members consid-
ered it important to include a grouting
contractor in the planning, and several
were interviewed.
There were few absolute requirements
other than experience with, and ability
to mobilize for, both compaction and
permeation grouting, and real time
computer monitoring with the origi-
nal data provided in non-proprietary
software such as Microsoft Excel.
The latter requirement was negatively
received by many, and was refused by
some of the prospective contractors.
It was this requirement that resulted
in the heated discussion at ICOG. The
paramount objection was basically
that some contractors have developed
expensive proprietary monitoring
programs which allow all to observe
the parameters on a monitor during
grout injection, and it is unreasonable
to require anything further.
Although it did not arise at ICOG, this
‘unreasonable to do more’ attitude is
actually a much wider issue. There are
commercial grouting data acquisition
systems with proprietary processing
software that allows no more than the
limited plot types embedded in the
software. And, perhaps even more
surprisingly, on larger projects with
Owner appointed ‘Review Boards’, it
is not uncommon to encounter review-
ers with a ‘we have always done it
this way and nothing more is needed’
viewpoint.
So, what drives these attitudes, and are
they reasonable?
Purpose of monitoring
Real time computer monitoring of
grouting serves three functions:
1. Display of grouting parameters
during injection to allow control of
the work, a) to ensure the best pos-
sible effectiveness (the result the
Owner is paying for) b) to main-
tain cost-effectiveness (operational
efficiency)
2. Providing original data for further
analysis and thereby enabling
optimization of subsequent work,
particularly if any unusual events
occurred during injection (in effect
allowing validation of the grouting
design/protocol/procedures)
3. Providing a record of the grouting
a) For pay-items
b) For project archives (used to
