Freeway access management activities have traditionally taken a nominal approach to safety. Acceptable safety performance is presumed to result from attaining some desired interchange or ramp spacing. This approach oversimplifies driver behavior and complex interactions between roadway geometrics, traffic operations, and safety. The objective of this paper is to quantify the relationship between ramp spacing and freeway safety, with safety defined as number of accidents, or accident consequences, by kind and severity, expected to occur during a specified time period.
Access control (Transportation)
III. RESEARCH PROBLEM STATEMENT
Access management treatments inherently reduce conflict points along urban arterial roadways. The reduction in conflict has translated to a reduction in crashes that has been documented in numerous studies looking at before and after conditions when access management treatments (i.e., raised median installation, driveway consolidation) are implemented. Crash rate reductions as high as 50 percent have been reported in these analyses.