Bike Crash

UT civil engineering professor Chris Cherry found a problem with bike crashes at a railroad crossing on Neyland Drive and decided to do something about it.

Two years ago, Cherry sat in his office in the John D. Tickle Engineering building and watched as bicyclists would repeatedly lose control of their bikes and crash onto the road below. Bikers had a smooth path until they hit the railroad and got their wheels stuck in the flangeway, which is the gap in the rails that allows a train's wheels to pass through.

Cherry set up a camera in his office window that would monitor the bike lane below. After the first weekend, the camera recorded three crashes in two days, and Cherry realized just how frequently bikers were losing control.

The video captured dozens of crashes. Some accidents even resulted in bikes falling into the street in the paths of oncoming cars. While most walked away with a few cuts and bruises, some people had to be carried away on stretchers and were injured for months.

“As far as we know, no one was killed at the site, but there was one that ended up in a wheel chair for three months,” Cherry said.

After recognizing the severity of the issue, Cherry began writing proposals to fund his research on how to fix the issue. Even now, he is bringing that research into the classroom to teach students proactive design in order to avoid fatalities.

“The hero, I think, is the engineer who goes in and solves the problem,” Cherry said.

Cherry presented his research to Jon Livengood, Knoxville’s alternative transportation engineer, who works to provide Knoxville with improvements for bicyclists.

Livengood immediately spearheaded a project that would fix the problem. The project included a new design that would be a cost-effective way to stop the crashes: the jughandle.

The jughandle is where the bike lane swings away from the road then swerves back to cross the track at just the right angle.

“Ideally, you want a bike to cross tracks at a 90 degree angle, but even with good engineering, that’s not always possible,” Cherry said. “During our research, we realized that you get the same results with 60 degrees.”

Cherry's research found that bike crashes decreased significantly when crossing at an angle greater than 30 degrees and were virtually nonexistent once they reached 60 degrees.

Once the city was provided with the number of an angle to begin construction, Livengood ensured the jughandle design was put into effect. The railway cooperated with the city to provide the space and organize the trains, and since the engineer on the project was able to use leftover asphalt from previous projects, the total cost of construction was $5,000.

“The biggest challenge was the riverbank. To do a perfect design, we needed more width off the shoulder,” Livengood said.

The result was the 60 degree angle between the flangeway and the bike lane as well as signs warning bikers of danger.

The city has also taken other measures to protect bikers, including the iBikeKnox app which allows bikers to map their routes and to drop pins where there might be potential hazards; the concept is similar to that of the driving app Waze. The app can note a pin and send an email notifying Knoxville’s Traffic Engineering Department of the issue.

Cherry’s students are also continuing their research to make sure the area stays safe by analyzing how effective the jughandle is in preventing crashes as well as how often people use it.

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