Bladen County Bridge No. 12

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Known by the state as Bladen County Bridge No. 12 over the Cape Fear River

What would you rather encounter on a paddle down the Cape Fear: this towering cage of steel and angles, or highway overpass? Which is a more attractive scene against the trees, water, and sky?

**Update: as of 2018, this bridge no longer exists. This page needs to be updated to reflect this.**

The 1950s were one of the more prolific periods of highway and bridge construction in North Carolina's--and America's--history (if not the most; I don't have the facts). Considering the amount of construction that was occurring, it is likely that designs were often chosen for practical purposes as opposed to their aesthetic quality and harmony with their surroundings; the same holds true today. I can only speculate at this time on the practical reasons for building a large single truss span over the river, as opposed to a simpler girder bridge like the 1957-built US 701 bridge upstream in Elizabethtown. Perhaps in 1952 there was not enough confidence in long girder spans, so a time-tested truss was built instead. The fact that the river was a minor shipping channel (there is a lock and dam not far upstream) and that the bridge is located in a bend on the river may have influenced the use of a design that has only two piers in the water, each located up against the opposing bank. Sinking piers into the middle of the river may have also been too expensive, time-consuming, or disruptive to river traffic. In any case. this structure was built towards the very end of the age of the truss era.

This structure is the original crossing at this location; it did not replace an older bridge or ferry. There is no mention of a crossing here in the NCDOT's 1938 detail map of Bladen County. It is easy to see why. The south bank (on the left side of the above photograph) is a pretty high bluff, while the north bank is swampy and low-lying. There is a relatively long set of approach spans on the latter side, in addition to a causeway and a few accompanying bridges that cross overflow canals. This was all constructed around 1952-53. It was originally signed as NC 141 and became NC 11 in 1975.

The bridge is a Pennsylvania truss (a.k.a. Petit truss). The best indicator of this type of truss is the diagonal, horizontal, and vertical members that meet together halfway up the structure. Together they look like a X (or a multiplication sign) that has been overlaid with an plus sign (X/+). It is the "+" that in part makes this a Petit truss; these extra members give the design added strength over its parent, the Parker truss. The Parker is also the source of its curved, or polygonal top chord, which gives the bridge its semi-arched shape. The majority of truss bridges built around this time were of the Warren variety, which is distinguishable by the "W" pattern of the diagonal members. Most connections are made with rivets, which have a more finished look to them than bolts. The bolts on this bridge are those that have been added later, such as those that hold up pieces of steel that replaced pieces damaged by trucks too tall for the bridge.

Today this bridge stands as an example of the NCDOT's hatred of truss bridges. This is a state that would much rather be building new highways than making sure that old ones are SAFE. A truss bridge, with its greater need for maintenance, stands for this. Their response to being shackled with this burden has been to do the absolute bare minimum, to the point that the bridge seems to be almost untouched from 1952. Virtually all of the original (probably lead) silver paint has flaked off (and into the water, into the fish, into the fisherman, maybe), leaving a surface of unsightly rust. The deck in one spot has been worn down to the rebar, and patched ineffectively with asphalt; when a car hits this at 65 MPH you can feel the bridge shake, so it's probably inflicting wear on the truss. The bridge has a sufficiency rating of 4, with poor conditions in all categories. The I-35W bridge had a rating of around 50, I believe. Yes, it has been allowed to become a really scary bridge. I wouldn't meet a tractor trailer on it, if I could avoid it.

Had this bridge been taken care of today it would have been quite sufficient. There is not a great amount of traffic crossing it and the lanes are sufficiently wide. But instead, they have let it stand to the point of near death, then will replace it with something that is "maintenance free." It will be a sad day when you will no longer see its skeleton peeking above the tree tops as you round the river bend, or approach in on NC 11. But that is how our governments work. In the meantime, I think they should lower the speed limit to 45 MPH or below. Doing so might encourage most people to drop their speed down from 65 to 55 as they go over the bridge; in turn they won't hit the holes in the deck as hard.

Update: NCDOT has slated this bridge, along with the similarly designed Tar Heel Ferry Road bridge, to be replaced. The project has a letting date of 10/1/2011. No design specifications are available, but it will undoubtedly be an "ugly concrete eyesore bridge (UCEB)." With the destruction of these two bridges there will be no more Pennsylvania truss bridges in the state.

Facts

  • Year built: 1952
  • Route Carried: NC 11
  • Crosses: Cape Fear River
  • Location: Bladen County, NC
  • Design: Pennsylvania through truss main span
  • 23 tee-beam approach spans
  • Length of main span: 251 ft. Total length: 1236.9 ft.
  • Inside width: 25.9 ft., two lanes
  • Average Daily Traffic: 3300
  • Sufficiency Rating: 4 out of 100
  • National Bridge Inventory ID: 17012
  • Coordinates: 34°23'48.72"N, 78°16'3.70"W

Pictures

  • Left: Shot of the main span, from downstream.
  • Center: Portal shot, facing north (Notice the shiny portal brace contrasted with the other rusty members. A truck probably struck the original one. Its connections are bolted, whereas all of the original connections are riveted.)
  • Right: Close-up shot of the middle panels of the truss.

  • Left: Oblique view, from the upstream side.
  • Center: Upstream shot of the bridge, taken using the red filter mode on my camera.
  • Right: The northern approach to the bridge, which consists of a causeway, canal bridges such as the one in the foreground, and an inclining set of approach spans leading up to the main truss span.

  • Detail of a center truss panel. The vertical, horizontal, and diagonal members that meet together at the middle connection form near right-angle triangles (the top chord is angled, so the top two triangles do not have 90-degree angles). The diagonals form an "X," while the horizontal and vertical members form a plus sign. Modern bridges simply do not have this intriguing geometry.

  • Left: Inside the truss span, showing the bracing and connections. Center: Detail of the floor beams, underside bracing, and lower chords. Right: Underside of the bridge, facing the north bank.

  • Left: The front post / upper chord connection. The "zigzagging" metal underneath the chords is called v-lacing.
  • Center: The connection between the lower chord, a vertical member, and two diagonal members.
  • Right: An upper chord connection, showing the great amount of rust, original riveted connections, and bolted repair connections.

  • The inept patching job done to the deck. When car hit this at a high rate of speed the shock causes the bridge to shake. After experiencing this I made sure I was off the main span when a car passed by.