INDIANAPOLIS, Ind. — Technology designed to allow more detailed monitoring of Indiana’s rural bridges is available from the state’s corn and soybean organizations, for use by county highway departments.
The Indiana Soybean Alliance (ISA) and Corn Marketing Council (ICMC) will make available technology that uses sensors to help determine correct load weights for county bridges. The Soy Transportation Coalition (STC) is also a partner in the program, which will be administered by the Indiana Local Technical Assistance Program (LTAP) at Purdue University.
County bridges are checked visually, though key load bearing points are also examined physically, said Ed Ebert, director of grain marketing for ISA/ICMC. Most bridges are examined every 2-4 years, he noted. The sensor technology advocated by the organizations allows for monitoring when traffic is crossing a bridge.
"The current way (of visual inspections) is not taking into account loaded traffic going over the bridge," he explained. "This technology is more precise than what’s used currently. It could find that a bridge, currently posted with a reduced load weight because of perceived issues, does need a reduced weight limit. Or it could find a bridge can handle more weight than posted."
The sensors don’t replace the need to visually inspect a bridge, he stated.
According to the 2015 State Bridge Sufficiency Rating Report, 1,398 of 13,090 bridges in Indiana maintained by county governments are considered structurally deficient. Also, 1,570 bridges have been closed or have weight restrictions.
Funding available from ISA and ICMC will be enough to pay for equipment to monitor 7-10 bridges, Ebert said. Depending on the size of a bridge, a monitoring kit may cost $10,000-$60,000. The equipment may be reused.
"It’ll end up being a very small sample (of bridges tested)," he explained. "It’s not as if we’re going to go out and fix this problem. At the county road level, we hope to help them identify what’s really important to them."
The use of the sensor technology will take the subjectivity out of bridge evaluation, said Mike Steenhoek, STC executive director. "We talk about the need for a greater degree of investment in the surface transportation system, including bridges," he said. "This is a way to utilize technology to make the evaluation of bridges much more accurate."
The subjective nature of bridge evaluation means occasionally, a bridge rated as deficient may actually be sufficient, Steenhoek noted. A correct bridge diagnosis can help local governments best use their limited resources to repair bridges found deficient, he noted. "Solving all our transportation problems isn’t just a function of money, it’s better stewardship of that money."
The problems with infrastructure and bridges are not just an issue for grain farmers, Ebert said. Grain elevators, processing plants and truck drivers hauling commodities are also dependent on them for their livelihoods.
"Farmers recognize the importance of being competitive in the global flow of grains," he said. "They recognize that one of the key leverage factors is reliability and consistency of supply. At harvest time specifically, this can create issues. The challenges start adding up."
Interested county highway departments should contact Patrick Conner with LTAP at 765-494-4971.
