SE Freeway IHSDM and Vissim Analysis
2022 Engineering Excellence State Finalist
Entering Firm: raSmith
Client: Wisconsin Department of Transportation
The Wisconsin Department of Transportation manages the state’s roadway infrastructure and is constantly working on projects to improve safety and traffic flow. With limited resources, future planning is a vital step and occurs years ahead of time to ensure the roads are built when needed.
raSmith partnered with the department in the busiest area of the state – the southeastern freeway system. The overarching goal was to develop a model that would present clear cost/benefit analysis of future freeway improvements. Interactive Highway Safety Design Model (IHSDM) is a program that can looks at a huge amount of data. The team focused on two elements: safety and the on/off ramps. The software can compare current stats with alternatives and find the best solution.
Another program used was a VISSIM analysis. This is traffic simulation modeling that looked at flow through the full system. A massive amount of data was collected from over 300 miles of freeway. Because this program and the IHSDM had never been used on such a scale before, the team developed new methods for processing this data and making it useful for the department.
The analysis will help the department pick the best improvements to fund in the coming years. These targeted solutions will maximize benefits to users and minimize costs – exactly what the client wanted.