CTI Academy Evaluation of Context Sensitive Methods to Influence Driver Behavior and Operating Speeds

The basic premise of a properly designed roadway is to consider the capacity and safety issues while addressing its physical and human environmental needs. To achieve a balance among the various goals, trade offs maybe needed. Design speed is a fundamental element in roadway design: a fact that had been underscored in the 2001 Policy for Geometric Design of Highways and Streets (Green Book) where it is now considered as a choice that determines the various geometric components (1). The desire to establish a design speed that is consistent with driver expectations and travel desires has been stressed as an important factor for determining this choice. Therefore, the relationship between operating and design speeds is a very important element in the design process. Often times, roadway designs rely on signing to enforce lower operating speeds while the roadway geometries encourage travel at higher speeds. The concept of designing selected roadways in a manner that will encourage drivers to operate at the desirable speeds has been recently revisited. This represents a roadway design philosophy that relies on the roadway design elements to encourage driving at the intended operating speeds. However, there is little knowledge of what design elements can effectively influence driver behavior and thus the drivers' choice of operating speeds. The objective of this research is to identify such design elements that could influence drivers: operating speeds and establish the potential magnitude of their influence. Virtual Reality simulations and video will be employed and drivers will be observed to evaluate the influence of these elements on their driving behavior. This work could be considered as pioneering the concept of design that could develop roadways where design speed will match the intended operating speed.