Down at the edge of West Philly where University City meets the Schuylkill River two cities exist. The first is a bright world of Penn students power walking across the Walnut Street Bridge to their morning classes. Below them union member park at PennPark and head over to the AFSCME Local 33 building, dodging Postal trucks as they head to the distribution center. What separates them is a very long bridge, not stretching the banks of the Schuylkill but stretching between 31st and 24th streets. (Images below from philageohistory.org)
Expansion joints keep the concrete bridge from buckling, but when the weather is as cold as it has been some gaps begin to appear. The photo below shows how a guardrail spanned (note the past tense) across the expansion joint, only to have one side of the bridge contract far enough to shear away the metal connection plate. I don’t know who added the zip ties but I cannot imagine that they serve any structural purpose.
In warmer weather the expansion joints start to disappear from view and experience.
This last image, of Walnut Street meeting 30th Street, now has a gap large enough to fit a Coke can in it. If the can is there tomorrow I’ll update this post with photographic evidence.