Traffic Accident Study On Milwaukee Expressway

Correlations between traffic accidents and geometric design features of freeways are presented. On through lanes, visibility relationships with geometric features along the through lanes are important. Evaluation and revision of weaving section design is needed. A short S type reverse curve on through lanes is not desirable. A sharp compound curve on interchange ramp is liable to cause more fixed-object accidents than any other type of accident. Proper design of both vertical and horizontal alinements at the junction of through lanes and interchange ramps is important and needs to be reevaluated. Width, length, horizontal alignment, and vertical alignment of entrance and exit ramps are found to have some correlation mainly with sideswipe and rear-end collisions. Weather, pavement surface, and light conditions are related with accidents in varying degrees. Pavement surface condition appears to be a better measure of accident likelihood than weather conditions. In summary, by judicious design of geometric elements, it may be possible to reduce traffic accidents by a considerable proportion.