Above - The Sergeant Aubrey Cosens Memorial Bridge on Hwy 11 after it failed in January 2003
(Photograph taken by Cameron Bevers - © 2003)
On Tuesday January 14, 2003, the deck of the Sergeant Aubrey Cosens Memorial Bridge
on Hwy 11 in Latchford failed. A record cold snap across Northeastern Ontario during
that week sent temperatures plummeting to levels well below -30 Degrees Celsius. At
about 2:45 pm, a transport truck passed over the bridge. Suddenly, the driver of the truck
felt his trailer load shift, and heard deafening popping sounds which he likened
to the sound of shotgun blasts. The sound which he heard were the rivets tearing
away from the steel cables connecting the overhead metal arch supporting the roadway
underneath. The driver made it safely off of the bridge before the deck collapsed
under the southbound lane of Hwy 11. Nearly one-half of the southbound lane of the
bridge collapsed, the ruins hanging precariously only a few inches above the
freezing, churning waters of the Montreal River.
The highway was immediately closed to traffic. The closure forced Hwy 11 traffic
to detour through Quebec, resulting in detours of up to 3 hours to get around the
failed structure. Luckily, pedestrians were permitted to walk across the icy
Latchford Dam. Within one week, construction had begun on a new temporary Bailey
Bridge across the Montreal River. A one-lane temporary bridge opened to traffic on
January 27, 2003, eliminating the lengthy detour, while a temporary two-lane structure
was opened to traffic on February 28, 2003.
In their analysis of the bridge failure, structural engineers determined that the deck
failed due to fractures in two of the hanger rods which connected the deck to the overhead
arch. Initially, only two hanger rods failed, but their failure triggered an adjacent hanger
to fail as well. The MTO's engineers concluded that "the main contributors to the fatigue induced fracture of the
hanger rods include: hanger pins that had seized, defects introduced in the hanger threads
during construction and steel that did not remain ductile in very cold temperatures. The
failure was progressive over a period of several years." (Quoted from "Sgt. Aubrey Cosens
V.C. Memorial Bridge over the Montreal River at Latchford Investigation of Failure: Final Report",
Ontario Ministry of Transportation, 2003)
Please click here
to see more photographs of the Latchford Bridge after the 2003 failure.
The failed Sergeant Aubrey Cosens Memorial Bridge was originally opened in October
1960, and was put back into service in 2005 after the deck was reconstructed. The
above photo was taken from the May 1961 issue of "Department of Highways News".
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