Bridges in Kent have had a lot of press in 2009. It was just about this time last year that a not so friendly CSX train decided to take on the Crain Avenue Bridge (the bridge won) but parts of the bridge stayed closed until February; this summer we replaced the Spaulding Drive Bridge and ODOT repaired the SR 261 overpass (over Plum Creek); Portage County replaced the Middlebury Road bridge (about a year after we replaced the Middlebury Road bridge over the railroad tracks); City Council approved a plan to repair the Mogadore Bridge/Culvert (also over Plum Creek); and as of this week we had the official kick-off for the Crain/Fairchild Avenue Bridge project. For a small town that’s a lot of bridge work. And after all that work, now it’s time to re-inspect the 14 bridges in Kent which will officially get underway this week.
Here are the bridge inspection results from 2008:
Here’s what those number ratings mean:
Kent Bridge Inspections
The Engineering Division of the Department of Public Service serves as the lead agency in coordinating the City of Kent’s bridge inspection program with the Ohio Department of Transportation (ODOT). Because bridge inspections require a very specific expertise, Kent’s Engineering Division contracts with a state certified bridge engineering firm to perform the necessary inspection services.
The City shares bridge inspection responsibilities with the County and the State. For example, the City is responsible for all bridges on “city” streets, and the state is responsible for the bridges on any of the limited access highways in the City, e.g., Haymaker Parkway bridge. Likewise, the County still has responsibility for some bridges in Kent, e.g., Main Street bridge, as do the railroads due to some unique historical agreements, e.g., Middlebury Road used to be railroad maintained.
Here’s the bridges that the City is responsible for inspection and maintenance:
1. Sunrise (over Fish Creek)
2. Spaulding (over Fish Creek)
3. River Bend (over Cuyahoga River)
4. Mogadore Road (Plum Creek culvert)
5. Fred Fuller Park (over Cuyahoga River)
6. Cherry Street (Plum Creek)
7. Allen Drive (over Fish Creek)
8. Admore Drive (over Fish Creek)
9. Middlebury Road (over the Cuyahoga)
Here’s the County bridges:
1. Main Street Bridge (over the Cuyahoga & RR)
2. Crain Avenue Bridge (over the Cuyahoga)
3. Middlebury Road (over the railroad tracks)
Here’s the State bridges:
1. Haymaker Parkway (over the Cuyahoga and RR)
2. SR 261 Over Plum Creek
City bridge inspection includes a thorough on-site review of the structural elements of the bridge. Detailed records and photographs are used to identify problem areas and to monitor changes in bridge condition over time. This data is summarized on a “Bridge Inventory and Bridge Inspection Sheet” that is completed by the inspection team for each bridge.
The Bridge Inventory and Inspection Sheets are completed in the field and then the engineers use the field data to derive a numeric bridge “sufficiency” rating for each bridge (0=closed to 9=as new, excellent). The use of this scoring methodology provides a quantitative indication of relative bridge condition and public safety risk.
Here’s a general overview of the inspection and rating process:
ODOT has minimum bridge standards and if bridge ratings fall below those safety standards the bridge may be classified as either structurally deficient and/or functionally obsolete. A structurally deficient bridge typically has significant problems (deterioration, corrosion, strength loss, etc.) in the load bearing parts of the bridge. A functionally obsolete bridge would be an older bridge that was constructed using a design that fails to meet current design standards, e.g., bridge rails substandard, lanes too narrow, vertical and horizontal alignment substandard, etc.
Public safety is the main objective of bridge inspections and because structural deficiencies represent a greater risk to public safety than functional obsolescence, the structural deficiencies tend to carry more weight than the functional elements in the sufficiency formula.
When the results of the 2009 bridge inspections come back I’ll be sure to share them.