Multiresolution Visualization Tools to Aid in Conducting Road Safety Audits

Typical road safety audits use site investigations in addition to historical data to make recommendations. Recent approaches have used simulation modeling to derive surrogate measures to analyze the potential for collisions, driving simulators to analyze human behavior, or other visualization tools to analyze geometric design characteristics. None of these tools can capture the dynamics of proposed changes that subsequently alter traffic patterns. Each proposed improvement has an influence on traffic patterns and must be captured at a regional level to determine whether vehicles choose the same path or defer to an alternative one. This study explored new methods to supplement the Road Safety Audit process. The study used visualization tools to assess the performance of each proposed improvement strategy by conducting a more thorough comprehensive safety study with multiresolution modeling methods in situations when suggested countermeasures would almost certainly redistribute traffic to alternative routes. A case study was selected in which an audit team performed a safety audit of a diamond interchange in El Paso, Texas, that experienced a high number of collisions during peak hours. The visualization of the proposed improvement scenarios helped the Texas Department of Transportation understand better how mitigation strategies would influence traffic flow in and around the study area or whether the proposed changes improved safety or merely shifted the problem to alternative locations. The use of visualization tools can help convey proposed improvements to the public.