US Bridges

I-55 (nb) over Sangamon Ave / Il 54

Good

Sangamon County, Illinois · I-55/IL54 Int NE Spi · Structure no. 084001500000000

Built
1963
62 years old, rebuilt 1995
Condition
Good
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
240 ft
4 main spans
Daily traffic
19,650
2023 count
Owner
State
State Highway Agency

About this bridge

I-55 (nb) over Sangamon Ave / Il 54 is a steel continuous stringer/multi-beam or girder carrying I-55 (nb) over Sangamon Ave / Il 54 in Sangamon County, Illinois. It was built in 1963 and reconstructed in 1995, so it is 62 years old, older than the Illinois average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 19,650 vehicles a day, roughly 25% of them trucks, projected to reach 19,089 by 2046. The structure is 240 ft (73.3 m) long and 74 ft wide.

Location

Open in Google Maps
CarriesI-55 (nb)
CrossesSangamon Ave / Il 54
LocationI-55/IL54 Int NE Spi
RouteInterstate 55
CountySangamon County
StateIllinois
Coordinates39.83129, -89.59295
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating64.3 US tons
Inventory rating38.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length240 ft (73.3 m)
Longest span73 ft (22.3 m)
Deck width74 ft (22.5 m)
Roadway width71 ft (21.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic19,650 (2023)
Projected traffic19,089 by 2046
Trucks25%
Lanes on structure2
Traffic directionOne-way traffic
CarriesOverpass structure at an interchange
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-55 (nb) over Sangamon Ave / Il 54 built?

It was built in 1963, making it 62 years old in 2025. It was reconstructed in 1995.

What condition is I-55 (nb) over Sangamon Ave / Il 54 in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2024.

How much traffic does I-55 (nb) over Sangamon Ave / Il 54 carry?

About 19,650 vehicles per day (2023 count), of which roughly 25% are trucks.

How long is I-55 (nb) over Sangamon Ave / Il 54?

The structure is 240 ft (73.3 m) long with a longest span of 73 ft (22.3 m) and a deck 74 ft wide.

Who owns I-55 (nb) over Sangamon Ave / Il 54?

It is owned by the State Highway Agency.