7/17/2019 MTO Scugog_Micropiles
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Year:
Technology:
2009
Micropiles
In contemplating foundation options for the twinning of Highway
7 over the Scugog River, Ontario’s Ministry of Transport (MTO)
had for years struggled with a dilemma: shallow foundations, that
would not jeopardize the existing bridge footings, would not suf-
fice to meet stringent new design codes (particularly with re-
spect to scour), and a conventional deep foundation, while meet-
ing code, would almost certainly disturb or damage the existingstructure.
The solution to this dilemma was micropiles, a deep foundation
system capable of being socketed into bedrock in close proximity
to the existing bridge’s spread footings without risk of damage to
the existing bridge’s spread footings. In late 2009, Geo-Founda-
tions, as subcontractor to Aecon Construction and Materials Ltd.,
constructed 38 micropiles as the foundations for 2 in-river piers
for the twinned bridge at Lindsay, ON. The work was staged from
barges, and all drilling took place inside fully flooded cofferdams.
Each micropile was socketed 7.5 metres into rock and reinforced with
273mm permanent casing and galvanized 57mm /517MPa threadbar
Pre-production static compressive and static tensile load testing was
performed on sacrificial piles on dry land, and post-production load
testing was performed on 4 piles inside the dewatered cofferdams
MTO Scugog River Bridge
GEO-FOUNDATIONS CONTRACTORS INC.302 Main Street North, Acton, Ontario, Canada L7J 1W9
Toll Free: 888-846-7858 Phone: 519-853-3216 Email: [email protected] Web: www.geo-foundations.com
The East Pier piling template
Micropile construction ongoing at the West Pier
Pile cap construction inside the dewatered East Pier cofferdam
Case Study