As more and more of Ontario's freeway infrastructure ages, Ontario (and I am sure other jurisdictions) are looking at more innovative bridge replacement technologies.
This weekend, Highway 417 (the Ottawa Queensway) will be shut down this weekend in order to replace the Kent Street bridge. The old bridge will be lifted off of its bearings, and then moved off-site for demolition. A new bridge that has already been constructed on a nearby vacant parcel will be wheeled into place over the weekend and then will be incorporated into the existing highway.
It's a very neat project, and is something that has been done a fair a bit in recent years in Ontario:
http://www.ottawasun.com/2015/10/09/kent-st-bridge-replacement-set-for-oct-24-25
http://www.cbc.ca/news/canada/ottawa/kent-street-bridge-replacement-on-queensway-delayed-province-says-1.3228969
An additional and similar replacement project was carried out on the 401 in Cornwall in recent years as well:
http://www.standard-freeholder.com/2014/02/24/new-process-for-replacing-overpass
This thread talks about some of these rapid replacements that have already occurred in the US, along with some videos of the process.
https://www.aaroads.com/forum/index.php?topic=13354.0