Vedder Bridge Replacement

ACEC-BC Award of Merit

World’s first steel arch bridge launched using the kingpost method

As part of the design-build team with Emil Anderson Construction Inc., KCB provided the structural, geotechnical, hydrotechnical engineering and construction engineering services for the new Vedder Bridge, and for demolition of the existing bridge over the Vedder River in Chilliwack, B.C. The Vedder Bridge is the world’s first steel arch bridge to be launched using the kingpost method.

Challenges

  • Old bridge was a steel through-truss built in 1947, deficient in clearance above flood water and deteriorating
  • Arch structure was not strong enough to be cantilevered 60 m without support on one end
  • Demolishing old bridge not suitable at this environmentally sensitive site and would have extended project schedule
  • Insufficient vehicle capacity during rush hour and weekends at north end intersection

Solutions

  • New bridge with higher clearance
  • Kingpost cable system used to provide localized reinforcement of tie girders and temporary support
  • Continuous longitudinal tie girders on south side span used as launching “nose”
  • Kingpost system modified and re-used to “de-launch” old bridge, reducing work over salmon-bearing river, resulting in low-risk solution for client
  • Approaching roads upgraded and new roundabout intersection built to provide greater travel capacity and improve safety

Successes

  • World’s first steel arch bridge launched using kingpost method. Precast deck panels were used as launching counterweight and formwork, reducing project cost and environmental footprint
  • Design-build project delivery method offered unique opportunity to develop cohesive and efficient bridge design package for client
  • Innovative demolition method eliminated temporary supports in river and reduced risk of lead contamination from components falling into river. Project schedule and cost were thus significantly reduced
  • Safe and convenient access for tourists and residents to popular lakes, contributing to community development

Paper:

Hamersley, B., W. Wu, J. O’Reilly. 2017. “Creative Construction Method for an Attractive Tied Arch,” in 39th IABSE Symposium – Engineering the Future, September 21-23 2017, Vancouver, Canada.

If you are interested in obtaining this publication, please email library@klohn.com.