Interesting to see if rivets were the proximate cause. I thought that
the bridge dropped fairly straight, and if that's so, one plate failing
might cause a twisting force... Let's let the NTSB figure this one out.

Too_Many_Tools wrote:
interstate bridge were originally attached with rivets,

If the construction material is so heavy, why not pile it up off the
bridge and use a conveyor belt to move it? One benefit would be much
reduced heavy dump truck travel onto the bridge. Set the pile up on the
side opposite the construction, and work toward the pile, shortening the
conveyor belt as you go. Concrete might be moved via a pumping system
akin to what they already use with construction.

Dunno about asphalt, as I've not seen any other movement techniques
other than dump trucks.

Construction crews had piled up sand and gravel on the bridge as they
prepared to pave a 520-foot stretch of two southbound lanes