Green Bay driver were treat to an unwished-for surprise yesterday , when the discovery of a dramatically sagging wharfage on the heavily trafficked Leo Frigo bridge ( named after a cheese magnate , because Wisconsin ) forced itsindefinite gag law . The incident coincided witha young AP reportabout the deteriorating state of American Harry Bridges , which seems like a repeated source of internal hysteria these daytime . But we should n’t regress to river - ford just yet .
The recentAP reportlooked at 607,380 bridge base on the late study by theNational Bridge Inventory , a database that the Federal Highway Administration uses to keep track of every American bridge and burrow that hold railroad car traffic . The NBI rates each anatomical structure on a scale from one to ten , and categorize them using terms like “ structurally deficient , ” meaning there ’s some defective component , or “ functionally disused , ” which mean there ’s a non - morphological defect . The NBI weigh to cities and states because it helps determine whether or not they ’ll receive federal fund to serve recreate their bridgework — but as of tardy , it ’s become a bellwether for critics who fence we ’re not doing enough to renovate our age base .
Leo Frigo by Todd Sanders onFlickr .
According to this year ’s report card , 65,605 American bridges are structurally deficient and more than 20,000 are “ fracture decisive . ” It sparked XII of other article , mostly detail the specific bridges in each state and metropolis that made the vital leaning . While there ’s for certain no one indicate that we should n’t spend to repair aging infrastructure , there were also some resist voices in the gang — mainly , applied scientist who argued that the report misinterpreted the NBI assortment organization .
For illustration , the “ fracture critical ” designation refers to bridges where , if one particular reinforcement fails , the entire structure could be at danger . As many charge out , even brand name - new bridges can be take for “ fracture decisive ” for designing reasons . span engineer Andrew Hermann had the pursuit to say toRaw Story :
There ’s a little twisting in those facts . Yes , we have over 65,000 bridges that are structurally deficient and over 20,000 that are fracture critical , but break critical is really an engineering science condition . A bridge circuit could be declare structurally deficient because of its deck , because of the piers that concur it up , because of the watercourse . It could also be due to an analysis of the structure and the superstructure , but there ’s five category , of which two would only put on to the geological fault critical . The deceptive thing is that a span could be structurally deficient for a number of reason way beyond the fracture decisive .
In Wisconsin , where this calendar week ’s closure consume position , the NBI singled out 60 bridge circuit as “ structurally lacking . ” But according to local news reports , Leo Frigo , was n’t on that inclination ; it was deemed tolerable at the last review , though there were small fissure observe . For now , the DOT will inspect it again to find out whether something was lack — or whether this is a new development .
Either means , today ’s tale proves that keep track of every bridge deck in the US is a hugely complex ( and long - term ) logistic incubus — and neither the media nor the NBI can predict every unsuccessful person .
Lead look-alike : screen door shot byABC 2 WBAY .
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