Development of Resource Allocation Strategies for Operating and Maintaining Traffic Signal Systems

Abstract

Functional vehicle detection and signal system communication are essential for a traffic signal system to execute its intended coordinated signal timing plans. The degradations of vehicle detection and signal system communication could impose barriers to successful operations of a traffic signal system. To achieve and maintain an acceptable operational level set by a traffic agency, an agency has to prioritize its resource allocation. This paper first introduces the concept of traffic signal system performance. It defines a traffic signal system degradation index which measures the proportion of increased travel time attributable to failures in detection and communication components with respect to the total observed travel time of a traffic signal control section. The paper uses the degradation index and traffic simulation to evaluate the effectiveness of major strategies to improve vehicle detection and signal system communication. These strategies include upgrading detection technologies, improving the responsiveness to detection and communication repair work, providing adequate training, increasing the frequency of inspection, and installing a global positioning system (GPS) clock to maintain synchronization of the time clock in the controller. Finally, recommendations for optimal allocation of operation and maintenance resource allocation strategies for traffic signal systems are provided.