Feasibility of Portable Traffic Signals to Replace Flaggers in Maintenance Operations

The purpose of the research project was to explore the use of portable traffic signal technology as a means for improving the efficiency of two-lane rural maintenance operations. The research findings are based on limited field testing of portable signals in actual routine pavement maintenance work. Issues such as work zone design, driver comprehension, signal operation, and signal equipment features are discussed as they relate to this particular portable signal application. The findings have been used to develop guidelines for the use of portable signals in maintenance operations in Texas, particularly with respect to setting up work zones and developing signal timing parameters. These recommendations are also documented in a separate implementation guide developed for field personnel. Current provisions of the Texas Manual on Uniform Traffic Control Devices do not fully address the technical and practical aspects of short-term application of portable traffic signals, and proposed revisions are presented in this report. Equipment features that support short-term usage of portable signals are also discussed. Finally, future research needs in the areas of work zone speed variability, motorist information signing, short-term pavement markings, and in-zone vehicle detection are discussed.