Roads/Highways

This report is divided into two parts:•Part I - Highway Traffic Data Sensitivity Analysis in Systems Approach. This work has been conducted by Dr. Xiao-Yun Lu at California PATH, U. C. Berkeley.•Part II - Empirical and Analytical Results for Sensitivity to Loop Station Spacing. This work has been conducted by Benjamin Coifman in Civil Engineering, Ohio State University.Since the aspects of the problem considered and approaches adopted by the two are different, it is thus necessary to separate the report into two parts. Each part is self-content.

The two most common types of high occupancy vehicle (HOV) lanes in California are continuous access, prevalent in Northern California, and buffer-separated limited access, prevalent in Southern California. This report describes the evaluation of operational performance of HOV facilities in several regions in California with different access types as well as a before-after comparative study of California facilities where access types were converted in recent years. A set of performance measures were defined and selected to indicate how well the HOV facilities achieve intended goals –...

This Appendix documents the details of the Intelligent Vehicle Highway Systems (IVHS) benefit analysis DEMOS models and provides the PATH user information about what is contained in and how to use the models. The object of this study was to structure an approach to evaluate the relationships of the top-level IVHS goals to the implementable actions and assess the relative benefits of those actions. The DEMOS model has been used as a tool to analyze selected IVHS actions with the goal of determining the key driving parameters through the use of sensitivity analysis.

We investigate the effect of a number of design alternatives on the safety and capacity of an Automated Highway System. Our methodology makes use of two computational tools, designed to highlight the fundamental limitations of the vehicle dynamics, sensing and control strategies and inter-vehicle communication. The first tool produces the minimum spacing necessary for two vehicles not to collide, as a function of their state and capabilities. The second tool investigates the multiple collisions that may occur in a string of vehicles if the spacing requirements of the first tool are...