1900’s bridges

A bright blue iron bridge

/ Roadtirementvintage / 5 Comments

Normally old iron truss bridges are painted in shades of green. Not this one, Shelby County Bridge #117 on CR 600 S. Bridgehunter.com has a 2010 photo showing a rusty green, but a 2016 shot shows a shiny bright blue paint job.

Approaching on CR 600S

The first bridge over Conn’s Creek at this location was a 16′ tall Pratt through truss built in 1892. Ironically it got a new concrete deck in 1912. The irony comes with the historic and horrific disastrous flood of 1913 which washed this bridge away. The original concrete abutments and wingwalls survived the flood and now support the replacement 7-panel, riveted Warren pony truss bridge. This bridge was built in 1925.

Looking at Conn’s Creek through truss

Truss outriggers and abutment and wing wall

Riveted hip connection

Diagonals, side rails and deck grate

You can see all 7 truss panels and deck grate

It is quite a visual as you approach this bright blue iron bridge. Like referenced above, you usually see green iron bridges, not blue. This is, however, a very nice bridge that spans a pretty little country creek.

For those of you interested in truss design details, HistoricBridges.org describes the design and structure: Concrete abutments and wingwalls support the single-span Warren pony truss. The riveted structure extends 87’6″ in seven panels. Its all-interior verticals are manufactured from pairs of angles riveted together with stay plates and reinforced with external sway bracing. Its diagonals are made from a pair of angles (doubled in the outer panel) also riveted together with stay plates. The I floor-beams are riveted to gussets and the verticals above the lower chord and carry the concrete deck. The weight and varied size of the diagonals, the placement of the floor-beams, and the integration of knee or external sway braces into the verticals indicate a late stage in the design of all-riveted Warren pony trusses.

 

Discovery of an Indiana iron bridge

/ Roadtirementvintage / 16 Comments

While following our map/directions app on the way to another historic bridge we were pleasantly surprised when we came up to another old iron bridge. This one has a lower profile, with no superstructure overhead. Typical of lots of smaller iron bridges, the deck is made of open grating that lets you look through the floor to the water below.

The approach

Note the angled supports

Detail of connection

Note damage at end of lattice piece

Looking over North Fork Salt Creek

 

 

 

 

 

 

 

 

 

 

This bridge, tagged Brown County Bridge #33, known to locals as the Green Valley Road Bridge, is an iron pony truss design. The bridge spans the North Fork of Salt Creek. The nearly 90 foot long span was constructed in 1915 by the Cambria Steel Co. of Johnstown, Pennsylvania. Cambria was a very prolific builder in many midwestern states at the turn of the century.

Open grate bridge deck

Probably needs an engineer to have a look

 

 

 

 

 

The Green Valley Road runs through a beautiful part of Brown County, one of Indiana’s most visited counties. This small bridge adds to the charm of the road and surrounds. It is eligible for the National Register of Historic Places. The structure could use a coat of paint. Some rather noticeable damage has occurred on one side of an approach. This damage may or may not be structural and hopefully is not hazardous to the bridge.