The Connecticut Transportation Safety Research Center has received a five-year extension from the Connecticut Department of Transportation for their project to develop a customized highway safety analysis tool for improving the safety of Connecticut’s roads.
Since 2015, the Center, located at the University of Connecticut’s Connecticut Transportation Institute, has been developing a data-driven process to determine the most effective way to approach road safety problems.
This extension will allow UConn’s research team to expand the capabilities of the current system.
The tool developed under the current safety grant and the new five-year grant is the “Connecticut Roadway Safety Management System (CRSMS)”, which is different but closely related to the “Connecticut Crash Data Repository” tool.
Using crash data, traffic patterns and road features, the CRSMS tool identifies the locations with the highest potential for safety improvement.
The tool helps engineers diagnose the reasons for safety issues. They then craft a short list of countermeasures from a list of more than 8,000 provided by the Crash Modification Factors Clearinghouse, a massive database by the Federal Highway Administration.
“The tool is a tool,” Shanshan Zhao, the principal investigator and project manager, says. “It still needs a lot of engineering judgment.”
While the tool primarily focuses on the engineering side, looking at how to improve the roads themselves, the Center will begin expanding the tool to include systemic and behavioral modules.
Systemic analyses look beyond safety measures that can easily identify hotspot crash locations but may neglect rural roads where serious crashes are often spread out.
“It’s a more proactive way of identifying potential locations for improvement,” Zhao says.
The behavioral analysis tool will be an important addition as approximately 90% of crashes are related to driver behavior.
“There’s a lot more people can do on the behavioral side than the engineering side so this is very important,” Zhao says.
The Center is filling in gaps of local roadway data to create a fuller picture of the safety of Connecticut’s roadways.
“We’re spending a lot of time collecting the proper data,” Zhao says.
While local governments are not yet using the tool in the same way as Connecticut DOT, they are indirectly benefiting from it as the state uses it to inform their decisions about which projects should be prioritized.
The tool also helps researchers perform cost-benefit analyses. Engineers must weigh the safety benefits of a given measure versus the cost of implementing it. The tool generates a ratio of the benefit to cost for each possible solution.
“At the end of the model they have a good idea of which treatment has a higher benefit over the costs of this countermeasure,” Zhao says.
Given budget restraints, there will always be more projects than the state can afford to fund. The cost-benefit ratios can help the DOT find the optimal combination of projects that will provide the greatest overall benefit within budgetary constraints.
After a countermeasure has been implemented for a few years, the tool analyzes the data again to determine how effective it was.
“The goal is to use advanced analysis methods to do the before and after analysis and check the effect the implementation measures are having,” Zhao says.
These analyses provide a guide for future investment as researchers and the DOT have real data on the impact of certain measures.
This extension of the grant will allow researchers to continue making methodological and technical improvements to the tool.
Because of their close relationship with Connecticut DOT, the researchers get timely feedback on the software from employees using it on the job. This allows the team at UConn to improve the tool in real time while simultaneously developing new features.
The Center will incorporate the latest recommendations from the upcoming edition of the Highway Safety Manual. Several members of the team have direct experience working on related projects funded by the National Cooperative Highway Research Program.
“We wanted to make sure safety projects in Connecticut are following the best and most advanced practices nationwide,” Zhao says.
Connecticut is a nationwide leader in highway safety. Zhao says other states can look to Connecticut’s tool and practices to guide their own projects.
“We want the effort and time we spend on the projects to benefit not only Connecticut, but other states that are interested in the best practices in highway safety analysis.” Zhao says. “We’d like to build a model here in Connecticut.”