Rural Expressway Intersection Characteristics that Contribute to Reduced Safety Performance

Expressways have been constructed in many states as a way to increase mobility without the expense of a full access-controlled or grade-separated facility. In most cases, it was assumed that these segments of highway would produce mobility and safety characteristics similar to other access-controlled facilities. However, recent research has found that there are problems with the safety performance of these systems associated with conventional at-grade, median-opening intersections. Although past research has been completed to examine the nature of crashes on these facilities, it is the purpose of this study to continue the research and analyze the common characteristics of the intersections. The intersections studied in this research were located throughout the state of Iowa. The objective of these analyses is to identify the major contributing factors that create problematic intersections in the state of Iowa.