Article content

Constructing the new Walterdale Bridge is like tuning a harp, or building a bicycle wheel. Sort of.

On this bridge — what the city calls its most complex infrastructure project to date — it’s easier to use analogies. The physics involved might make engineering students shudder.

We apologize, but this video has failed to load.

tap here to see other videos from our team. Try refreshing your browser, or Building new Walterdale Bridge like assembling puzzle made with 125-tonne pieces Back to video

Think of it: steel cables thicker than your fist stretched by several inches as crews poured the concrete deck. Steel arches bent into a target shape as the cables were tightened one by one, like tightening spokes to shape a bike wheel.

Korean steel fabricators — widely criticized for delivering a year behind schedule — didn’t just deliver 125-tonne puzzle pieces, they delivered 42 pieces deliberately misshapen so the forces within the bridge could form it into the right geometry.

Photo by Shaughn Butts / Edmonton Journal

“Every one of those pieces did fit; I was really surprised,” said Jim Montgomery, lead designer and engineer with the local firm Dialog, who gave Postmedia a year-end tour with city project manager Ryan Teplitsky.