Bridge segments ease on down the road
Posted on May 2nd, 2008 – 1:45 PMBy Roadguy
Roadguy spent this, uh, beautiful spring morning down by the riverside, where the first precast segment of the 35W bridge headed down West River Parkway (click on image for larger view, then click again for ridiculously close-up view):
Nearby office workers watched as the 198-ton piece of concrete box girder eased on down the road to Bohemian Flats. The segments will be stored there until it’s time for a barge crane to hoist them into place over the river. (Story I wrote is here.)
If I counted right, The flatbed trailer had 64 wheels. It was quite an operation.
19 Responses to "Bridge segments ease on down the road"
Seeing that picture makes me want to bust out my lego bricks and build something with these.
Am I allowed to think that’s really stinking cool? Because it is.
I’m glad I double-clicked on the image. I thought the thing at the right was also for the bridge, and it’s not. Gotta get my glasses on.
Anyone know what those steel-looking wires that are sticking out at the top right are for?
I watched part of a parking ramp get demolished in South Mpls (near Abbott Northwestern Hospital) by a big-tooth machine on Monday and there were green wires everywhere.
Is that stuff in there because the cement needs it?
ltdg: All those wires sticking out are rebar to strengthen the concrete. I think they’re sticking out the one side and not the other because that’s the center of that bridge half. Each set of lanes has two of these box girders side-by-side.
Check out what appears to be a manhole in the top-center of the segment. I pity the fool that goes into that thing!
Also I’m wondering about the two downspout pipes shown on the side… Anyone know if these get hooked into other pipes once the bridge is assembled? Or does water flow freely along the bottom of the “tunnel” cavity?
If you notice, the far side of the segment has the rebar already bent up for the outer barrier (guard rail).
Oh and green bar is rebar coated with epoxy to keep it from rusting.
I don’t think it’s a manhole — I have a photo I shot from above, and that circle isn’t visible. (I’ll try to post it at some point — on deadline at the moment.)
The two vertical pieces of metal visible inside the segment on the lefthand side aren’t downspouts (if those are what you were referring to). Those were used to lift the segment off the trailer.
Is that PVC pipe (the white ones at the top)? What will they be used for?
Cables connecting the segments to each other and to the rest of the bridge will run through those holes (I can’t remember if they’re PVC or what at the moment).
Here’s what I don’t understand: How do they hold the bridge up, until they can get all the segments in place - so they can thread the tensioning cables?
Falsework?
I don’t want to hear anything about tensioning cable rusting!
maybe they should run the lrt down the inside of the bridge. its big enough.
What WILL be inside all that open space….nothing?
That is not a manhole. It is most likely the location of the anti-icing spray head.
No falsework on the main river span. It will be done doing cantilever construction. You have to make it out there in June and see it for your self. It will be an awesome site to see.
Open space will be inside the open space. Thus the name, “box girder”. It does allow for inspectors to travel along inside the span looking for crack nicely though. That’s how the cracks in the Wakota bridge under construction were discovered as I recall.
I love seeing these in-progress photos!
I wonder what kind of gas mileage a rig like that gets?
I imagine they report gas mileage for something like that in gallons per mile. 
Why only a few cables at bottom of box where the box is under tension load?
And many, many cables at top where load is compression (+ shear)? Concrete takes huge compression loading but needs cable to take tension.
