Congratulations to WA DOT and contractors.
Less than 1 month after the collapse, the bridge will reopen.
http://seattletimes.com/html/localnews/2021218061_skagitbridgexml.html
Paul in PA
For those who are curious it appears to be two triple-truss-double-story (triple-double) Bailey bridges located side by side.
I was a 12B Combat Engineer in the Army. We practiced building and launching Bailey bridges more often than I would have liked. We usually built single-single and double-singles and launched them across wide shallow ponds or man-made valleys for practice. Typically a bridge was built by a Company size unit (approx. 100 men) in a single night starting after dark and finishing before dawn. I'd be curious how quickly the military could've spanned this gap in a have to situation.
Out of curiosity I looked up the Army's manual for the Bailey Bridge. For a triple-double the max span is 180 feet. The manual indicates that a crew of 6 NCOs and 92 Enlisted working in daylight with only manual labor should be able to build the bridge in 9.5 hours. A 200 foot triple-triple requires 7 NCOs and 103 Enlisted + one crane due to the height of the third level and still only requires 20.5 hours to build.
Bailey bridges are very adaptable to different spans.
The county road dept. uses them on flood damage sites and construction detours.
Small crew...couple operators and a couple laborers.
Shorter spans and single lane.
