The Bridges of Historic Bridge Park

 Today, I'm going to show you the part of my hike on Tuesday that I didn't want to miss. It's at least my third time there, but this time, I made a particular effort to get better pictures of the various bridges. This is a county park, and they have moved 5 obsolete bridges to the area which is adjacent to a railroad culvert/bridge which is also part of the display. This is a wonderful engineering "museum" you walk through on the North Country Trail. I wanted to take time to look up more information about the various bridges. Don't think I know all this stuff without looking it up. I am getting a little better at recognizing the bridge styles, but only really know a few of the oddball ones by heart.

First up is the Charlotte Highway Bridge, built in 1886 by the Buckeye Bridge Works of Cleveland, OH. It is a metal 11 Panel Pin-Connected Whipple (Double-Intersection Pratt) Through Truss Bridge. Basically, that means there are 11 quadrilateral panels of the deck, and that the metal superstructure with various designs of the uprights and diagonals completely surrounds the deck (through truss). Whipple is the name of the arrangement of the diagonal supports. In this case, you can see that they basically go from the outer top corners of each panel to the inner lower corners of the NEXT panel, not the same one. This was a common design for long bridges in the 19th century. Historic Bridges organization rates this bridge as 10 in local significance, and an 8 on the national level.

Here is the underside of that bridge. This one has been reinstalled as a pedestrian bridge over the park road, so you can really see it. Each of the large squares is one panel.

Next, we'll do the 133rd Avenue bridge from Allegan, built in 1897. This is a half-hip pony truss bridge with four panels. "Pony" because the trusses are above the decking, but not over the top of the decking. You can count for yourself that there are four panels in this one. It's a "half hip" because there is no vertical brace where the angle of the top rail meets the horizontal part of the top rail. This used to be a very common bridge type, but now there aren't many left. It got a local rating of 8 and national of 6.

This is the bridge that spanned 20-Mile Rd in Calhoun County. It was built in 1906. It's a metal five-panel Rivet-Connected Pratt Full-Slope Pony Truss. I don't know what the full-slope part means, but you can see that it's different from the one above because there is a vertical support from that top angle. It's local and national significance are both 6. It's connected with rivets, not pins.

The Gale Road Bridge from Ingham county was built in 1897. It is a metal 7-Panel Pin-Connected Pratt Through Truss. This was a very common kind. "Pinned" means that the corner pieces all fit together and were held in place by a threaded pin that was slipped through when the holes were aligned, and then nuts were screwed on the ends. These were easy to assemble in the field. The diagonals go from the outer top corner of each panel to the inner lower corner of the same panel. It was built by the Lafayette Bridge Company of Lafayette, Indiana. It gets a local significance of 8 and national of 7.

This is the Bauer Road Bridge from Clinton County, built in 1886. It's a metal 6-Panel Pin-Connected Pratt Through Truss. So now you know that it has diagonals that go from one corner to the other of the same panel, that the structure makes a "covering" over the decking, and that the corners are held together with pins not rivets! This has a local significance of 8 and national of 7. It was built by the Penn Bridge Company of Beaver Falls, Pennsylvania.

I like that it has some decorative elements as well.

Finally, there is the railroad bridge. The train line is active, and carries a regular Amtrak run from Detroit to Chicago, and occasionally freight.

This is called Dixon's Bridge. Although it is very unusual, it only got a local rating of 6 and a national rating of 4. It was built in 1892. It's a semicircular stone arch bridge. The larger arch was for the road (which is now the bike path/trail), and the smaller arch carries Dickinson Creek.

One really odd feature is that half is stone, and then it was apparently expanded with the other half being concrete, possibly to carry a double-track railroad. An historic postcard from 1909 shows both parts.

I really should have taken a picture of the facing on the stone side. Next time!

You can find out about many old bridges at HistoricBridges.org

Don't know what that little bug was I had yesterday. I slept 14 hours, ate soup and juice all day. I'm fine now. Maybe not ready to take a hike, but all is well. I edited and wrote.

See Calhoun County Trailway