Knowledge Base on Semi‐Actuated Traffic‐Signal Control

The efficient use of semi‐actuated control requires careful selection of phasing plan, timing design, and detector configuration. Computer simulation can be used to assist in the search for efficient ways of operating such a control, but it has not been widely employed by practicing engineers. Analytical methodologies for the operational design of signal control are potentially easier to use than are simulation models. Their development, however, has not reached a mature stage. The objective of this study is to use a simulation model to develop an easily accessible knowledge base for the use of semi‐actuated control at individual intersections. This knowledge base concerns semi‐actuated operations that rely on inductive loop detectors for presence detection of vehicles and that do not accommodate pedestrian timing. It focuses on the following aspects of the signal operations: choice of phasing plan, timing design for nonactuated phase and actuated phase, timing setting of call‐delay for delayed‐call detectors, and the choice between semi‐actuated and full‐actuated control.