This paper was presented at the "Geometric design and safety" session. These proceedings are available on CD-ROM. To improve road safety, roadway geometries are frequently modified based at black spots. The black spot remedial approach requires fatalities and injuries to occur before the needs and priorities of roadway improvements may be identified. This paper outlines a method to incorporate vehicle dynamics to detect, quantify and correct curve and sight distance roadway hazards at the design stage. The methodology is a reliability-based highway geometric design, similar to "limit state" design in structural engineering (1). A "racing car model" is proposed by the authors as the upper operating limit or operational capacity. The critical operating conditions are identified by the probability of design non-compliance for a defined driver as they approach the "race car" capacity. The safety performance measures allow design alternatives to be compared on a more efffective safety basis and may lead to highway designs for safety. (A)
Abstract