search
top

Trucks. Bridge. Physics. Guess What Wins?

In Durham, NC, there is a railroad trestle bridge that is owned by the North Carolina Railroad Company. The bridge was designed and built over 100 years ago, long before there were standards in road construction and bridge heights. With height of 11′ 10.8″ above the road surface below it, the bridge gets hit by trucks on the average of once a month. The railroad company installed a stout “crash bar” of very solid and heavy steel in front of the bridge to protect it. The result is that the bridge is safe and trucks that are too tall and drivers who think they can make it have their trucks sheered off, thus earning the bridge the nickname of “the Can Opener.”

To slow down the number of accidents, traffic engineers installed signs for three blocks before the bridge warning of the limited height. The signs are required by law to give the height as 2 inches below the actual height so the signs all say the bridge is 11′ 8′.

Even with the warning signs, drivers continued to slam into the bridge, ripping the trucks apart.

The bridge cannot be raised because it would be cost prohibitive and the road surface below the bridge cannot be lowered as there is a sewer line.

Faced with no viable solutions, traffic engineers came up with the idea of sensors that measure the height of a passing truck before it gets to the bridge and if the truck is too high, the traffic signal turns red and a huge LED sign lights up and flashes “OVER HEIGHT – MUST TURN” which one would think would alert truck drivers to the problem before they hit the bridge.

One would be wrong.

Here’s the latest accident:



The video comes from Jürgen Henn, who has an office nearby and runs the website 11foot8.com where he regularly posts the latest attempt by trucks and drivers to defeat the height and crash bar steel of the bridge. He even collects the remnants of metal from the crashes and sells them as art pieces.

The bridge is the subject of the documentary below.

(At around the 8:00 mark, there are people that are from the “Center for Advanced Hindsight.” We originally thought that was a prank, but it is a real place.)

You just have to wonder what the drivers of the trucks are thinking. Do they think that their truck will shrink or curtsy to get under the bridge? Do they think the flashing sign and the red lights don’t apply to them? Do they think that the crash bar of solid steel is going to lose in a battle with their aluminum cargo areas? Are they distracted drivers?

No matter what, watching the crashes is like watching a train wreck. You know what is coming an you still can’t look away because at the end of the day…..

…PHYSICS WINS.



Comments are closed.

top