The Texas Manual on Uniform Traffic Control Devices (TMUTCD) provides the definition of regular traffic generators based on four population types but not for major traffic generators (MTGs). MTG signs have been considered to supplement the overall signing system for highways, and can direct road users to important traffic generators, resulting in improved traffic flow operation and decreasing drivers’ frustration caused by missing an exit. These signs would better guide travellers on major highway "gateways" to crucial cultural, business, and recreational destinations, especially for those who are unfamiliar with the area. Minnesota, Missouri, North Carolina, and British Columbia in Canada have specific guidelines for MTGs in various forms; however, these guidelines are not applicable for direct use in Texas. It is imperative to establish MTG warrants that are suitable for the Texas environment. In this report, practices and manuals used in Texas and other states are scanned and summarized through a literature review, an engineer survey, and an MTG survey. Engineer opinions and the needs of MTGs were obtained in terms of the criteria, types of symbols used, and location and size of symbols/signs. Practices in other states and the opinions of responding engineers are synthesized through proposed fuzzy logic–based algorithms. Together with driving simulator tests and computer slide show tests, the preliminary recommendations about the types of symbols and location and size of symbols/signs for MTGs are then identified. (Author/publisher)
Abstract