Lacon Bridge, Lacon, Illinois
The Lacon Bridge is a continuous through bridge over the Illinois River on Illinois Route 17 at Lacon in Marshall County. Built in 1939, it is one of the oldest crossings of the Illinois River. The bridge was rehabilitated in 1990, and is tentatively scheduled for repairs to the structural steel, painting the entire structure, concrete repairs to the piers and abutments, and repairing the existing lighting in 2023.
This bridge has a distinctive appearance because its top chord and end posts visually seem comparatively smaller than one would expect to the point where they do not look much larger or heavier than the other truss members. As such, from a visual standpoint, all the members and chords on the bridge look to be about the same size. This is quite different from a traditional bridge of this design.
This is one of those bridges that looks exactly like a cantilever truss, with a variable depth truss forming "towers" over the piers, however it appears to lack hinges which means that it functions as a continuous truss, not a cantilever truss. As such, it does not have a suspended span. A series of steel stringer spans provide an approach to the through truss spans.
Marshall County, located in north central Illinois, is primarily an agriculture county. Lacon, the county seat, is the second most populous city in the county behind Henry with a recorded population of 1,878 at the 2020 census.
Sources: Wikipedia, HistoricBridge.org, and Marshall-Putnam Farm Bureau
Lacon Bridge, Lacon, Illinois
The Lacon Bridge is a continuous through bridge over the Illinois River on Illinois Route 17 at Lacon in Marshall County. Built in 1939, it is one of the oldest crossings of the Illinois River. The bridge was rehabilitated in 1990, and is tentatively scheduled for repairs to the structural steel, painting the entire structure, concrete repairs to the piers and abutments, and repairing the existing lighting in 2023.
This bridge has a distinctive appearance because its top chord and end posts visually seem comparatively smaller than one would expect to the point where they do not look much larger or heavier than the other truss members. As such, from a visual standpoint, all the members and chords on the bridge look to be about the same size. This is quite different from a traditional bridge of this design.
This is one of those bridges that looks exactly like a cantilever truss, with a variable depth truss forming "towers" over the piers, however it appears to lack hinges which means that it functions as a continuous truss, not a cantilever truss. As such, it does not have a suspended span. A series of steel stringer spans provide an approach to the through truss spans.
Marshall County, located in north central Illinois, is primarily an agriculture county. Lacon, the county seat, is the second most populous city in the county behind Henry with a recorded population of 1,878 at the 2020 census.
Sources: Wikipedia, HistoricBridge.org, and Marshall-Putnam Farm Bureau