What are the advantages of Substantive Safety Approach to Geometric Design?
The advantage of the Substantive Safety approach is the ability to have a quantitative assessment of the safety of design alternatives before they are built rather than after. The emphasis is on the application of safety research results to design decisions for application of the requirements and guidelines detailed in the 2001 AASHTO Green Book for curvature, lane width, shoulder width, grade and intersection. Successful Applications: States’ Results Demonstrate Success Several States have adopted the Substantive Safety approach to quantify safety of alternative designs in their design process: Iowa The Iowa Department of Transportation (DOT) has fully implemented the Substantive Safety Approach to project design by training all of the design engineering staff of their districts in a series of training workshops. Adoption of this new approach to difficult two-lane highway projects has allowed difficult high estimated cost projects to be adequately addressed in a reasonable cost contex