Special Saw, 'The Beast', Cuts Through Concrete Bridge Over Keystone Dam

Friday, April 18th 2014, 6:33 pm
By: Emory Bryan

The year-long project to replace the bridge over Keystone Dam is almost halfway finished.

Even though the work had to stop during extreme cold, one tool in particular is helping to speed up the work.

The job is massive by any measure -- replacing the deck and support structure of the bridge on Keystone Dam.

10/28/2014 Related Story: Highway 151 Over Keystone Dam Closed For Repairs

To add to the normal complications of construction, it wasn't built with rebuilding it in mind.

The process of dismantling and replacing it had to be engineered from scratch.

"We're on schedule and have experienced the usual construction issues of things we didn't expect, the unknown, but we're on schedule and think we've conquered most of the issues," Mike Nance said.

They're conquering it with some custom built tools - including a gantry-style 30-ton crane built just for the project.

It rides on rails that were added on to the sides of the dam.

That helps because every piece has to be lifted off.

Because of environmental concerns, nothing -- not a crumb of concrete -- can drop into the water.

It comes out in panels. They're about 22,000 pounds each. The saws cut it up, and the crane lifts it and place it on a flatbed truck and it's hauled off. In other words, the demolition is going pretty good.

Because of the way the bridge was built, engineers decided the only way to dismantle it was to cut it apart.

That's where this giant concrete saw -- The Beast -- comes into play.

With a blade 6 feet in diameter, it can saw all the way through.

It's water cooled, which keeps the dust contained. Workers vacuum up everything the saw throws out.

Tools help keep the finish line in sight.

"That is what they're waiting for and that date is, great anticipation," Nance said.

The demolition isn't done, but the reconstruction has already started on the other end.

The old bridge is right at 50 years old and the replacement should last just as long after it opens around Thanksgiving.