skyking
Lifer
- Nov 21, 2001
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VERY cool machine, but as mentioned, with Chinese building quality being what it is...what keeps those bridge deck sections from falling off the bridge pylons? (well...besides gravity) Maybe I just didn't see it in the videos, but USUALLY, when pre-cast sections are joined, there are several points to attach them to each other...and often, cables such as the stress cables SkyKing was talking about. (I've seen them build box girder bridges with a silhouette very similar to those from concrete, rebar, and plywood forms. (it's how MOST concrete bridges are built nowadays in the US of A) and when they're done pouring concrete, they run the post-tensioning cables through the bridge from end to end, pull a metric fuck-ton of pressure on them...and the center of the bridge lifts...bends...from several inches to a few feet, depending on design. It's pretty impressive to see.
They probably pour back a big diaphragm pour, maybe some mungo sized bolts through some imbeds.
The bridges I worked on were prestressed concrete beams joined by a diaphragm pour at the pier caps, and your typical bidwell-poured deck over.