Geotechnical News • June 2017
37
In 1982 members of the Canadian
Geotechnical Society conceived the
idea of a book recording the develop-
ment of geotechnical engineering in
Canada. Since a number of the early
practitioners were still living at the
time, foremost among them Bob Hardy
d Bob Legget, the approach was
intended to create “a living history ...
through the eyes and recollections of
living engineers, to show the human-
ity that underlies the development
of major geotechnical projects in
Canada.”
As this book is now out-of-print, we
will be publishing excerpts from it
over the next few editions of Geotech-
nical News. Ultimately, a pdf copy will
be available.
Geotechnical Engineering in Canada
An Historial Overview
Cyril E. Leonoff
Born in Leeds, Quebec, Samuel
Fortier (1855-1933) graduated in civil
engineering from McGill University
in 1885 and later received a masters’s
degree from this university. In Octo-
ber 1896 Fortier read a paper, “The
Storage of Water in Earthen Reser-
voirs,” before the Canadian Society of
Civil Engineers, which earned for its
author the Gzowski Medal, the senior
technical award of the society. In it he
anticipated the factors that would be
considered by a modern soil mechan-
ics engineer: “An intimate knowledge
gained from a close study and care-
fully made tests of the physical ...
and mechanical ... properties of the
materials ... the size and weight of the
grains, the amount of air-space they
enclose, the percentages of air and
water contained in these open spaces,
and the effects produced by moisture,
heat and frost, as well as the action
of such forces as gravity, capillarity
and evaporation [and] the mode of
compacting reservoir embankments.”
Fortier further recognized that “the
proper widths and slopes to adopt in
the building of earthen dams cannot
as yet be determined by mathematical
calculations [but] the dimensions in
each particular case must be left to the
good judgment, practical skill and the
knowledge gained from experimental
tests, of the designing engineer.”
Fortier is less well known in Canada
than in the Western United States, to
which he emigrated and gained repute
as a water works and agricultural irri-
gation engineer in Colorado, Montana,
and California.
In 1897 civil engineer Robert Brew-
ster Stanton, who had thirty years’
experience in the Rocky Mountain
region from Canada to Mexico, read a
paper before the British Institution of
Civil Engineers on the great landslides
that had occurred on the Thompson
River near present-day Ashcroft; Brit-
ish Columbia, at the time of construc-
tion of the Canadian Pacific Railway
in the 1880s.
Within a distance of some five miles
there were several large landslides,
six crossing the railway line, as well
as a number of smaller slips. Twenty
miles farther down the river, at a point
opposite Spences Bridge, there was a
similar large slide. Three of the slides
were of giant proportions. The largest,
the 100 million-ton Great North Slide
of October 1881, actually blocked
the river for 44 hours, causing a huge
flood. Stanton, after careful observa-
tions, attributed the slides to irrigation
of the silt terraces above the river,
which when saturated lost strength and
collapsed into the river. More recent
soil mechanics examination has indi-
cated that the silt is finely layered with
clay and that the seat of shearing may
have been in the clay. As both trans-
continental rail lines CP and CN still
traverse these slides, there is yet some
local manifestation of slide action on a
smaller scale.
The failure of the Transcona Grain
Elevator, built in the glacial Lake
Agassiz basin near Winnipeg, Mani-
toba is a classic case of shear failure of
a heavy structure on a raft foundation,
built on a thick layer of soft saturated
clay. Filling of the bins of the million-
bushel-elevator began in September
1913. When 875,000 bushels of wheat
were stored, a vertical one-foot settle-
ment was noted within an hour, then
the structure began to tilt to the west,
and within 24 hours came to rest at an
angle of 26° 53’ from the vertical. The
west side was 29 feet below and the
east side 5 feet above original grade.
The rigid monolithic structure, built on
a two-foot-thick reinforced-concrete
raft, showed little damage other than a
few surficial cracks. The elevator was
righted and underpinned by the Foun-
dation Company of Canada on piers
sunk 54 feet to the limestone bedrock.
COMMEMORATIVE EDITION
