VANCOUVER – Acrow Bridge has supplied a temporary, modular steel panel bridge that is being used during the replacement of the Montroyal Bridge over Mosquito Creek in the District of North Vancouver, B.C.
The old structure was a 60-year-old timber bridge that was both under-capacity and at the end of its useful life.
Because the existing bridge was in close proximity to a fire station, it was critical that the detour structure be in place before demolition began in order to provide continuous access for emergency vehicles, states a release issued by Acrow Bridge, adding the route is heavily travelled by commuters.
The rented two-lane TL24 structure from Acrow is 39.6 metres long by 7.3 metres wide curb to curb, with guardrails and a 1.5 metre sidewalk.
“The bearing to finished deck clearance at each end of bridge minimized the excavation required for foundation installation,” said Lyle Johnson, manager of field operations for Eurovia BC, in a statement.
The launching and erection of the bridge posed numerous challenges, the release indicates, because there was little room available to stage components onsite. The Acrow components were delivered to a laydown area four kilometres from the site and brought to the work zone as needed.
The team also had to deal with a confined work space. The build area for the bridge was limited to 12.2 metres by 9.75 metres on the west approach. The bridge was erected on rollers, with additional rollers on top of a temporary launching pier.
For the final launch, a large crane positioned on the east approach was attached to the east end of the bridge, which was then moved to its final position and held two metres above the east bearings while the temporary pier was removed. The bridge was eventually lowered and set on both abutment bearings.
The installation was completed in three weeks. It is anticipated that the temporary bridge will be in place throughout construction, which is scheduled for completion this summer.
The owner of the Montroyal bridge project is the Corporation of the District of North Vancouver and the contractor is Eurovia BC Inc. who selected Acrow Bridge, based in Bolton, Ont., for the job. The design engineers for the detour for Eurovia was All-Span Engineering & Construction Ltd. and McElhanney Consulting Services Ltd. The design engineer for the owners was WSP Canada Inc.