12-29-2016, 10:12 AM
This is the stop at Ottawa's VIA station. They have this "loop" road, sort of like you'd see at an airport, where you can endlessly spiral around waiting for someone to arrive. The Confederation line bisects the loop, underneath, and the stop is just a short walk away from the main station hall. It's going to look fantastic when complete.
Downtown, we drove right over top of the tunnel - and not a single road was [fully] closed. Minimal disruption here, despite a massive undertaking going on right below. This is actually where that huge sinkhole was!
So this looks familiar...
...but this does not! Ottawa has a couple of these spring tensioners (instead of weights) in the Belfast Yards at a few strategic locations. They have a spiral spring inside of them. Springs are no good if your goal is constant tension - force varies linearly with stretch on a spring. These devices compensate for that with a carefully designed spiral profile on the side, which does the actual winding. Brilliant! You can read more about them here.