Measuring Drivers’ Visual Attention in Work Zones

AbstractAssessing driver sensory and cognitive processes, and the effect of temporary traffic control devices upon those processes in work zones, can be somewhat difficult. Measuring vehicle speed, lane position, acceleration, braking, turning, etc. through in-vehicle instrumentation is easily accomplished, but understanding driver visual attention is much more challenging. For example, during construction projects, drivers often have difficulty identifying appropriate gaps for turning in order to access businesses, particularly at night. In addition, driveways are often delineated with channelizing drums that appear the same as all the other drums in the work zone. Researchers at the Texas A&M Transportation Institute performed a study of driver eye-tracking in work zones to determine if drivers could more easily locate specific business driveways if alternative driveway delineation treatments were used. The evaluation was performed using paid participants driving instrumented vehicles equipped with dash-mounted eye-tracking equipment. Primary measures of effectiveness (MOE) were: participants’ glance distributions at various viewing regions during driveway approaches and average glance durations at driveway treatments. Overall, the data showed that drivers’ visual attention was different when the alternative delineation treatments were used, evidenced by a statistically significant increase in the number of treatment glances at the alternative treatments. There was little difference in the durations of the treatment glances during the daytime, probably due to the prevalence of other visual cues that are readily visible in the daytime. But glance durations at the alternative treatments were longer at night, indicative of the success of the treatment in attracting attention to the actual driveway location. Overall, while differences in the MOE were less pronounced during the day, the alternative channelizing treatments generally performed better than the standard drum treatment at night

Evaluation of End-of-Queue Crash Mitigation Strategies at Flagging Stations on Two-Lane Roads

Project 0-6998The objective of this research project was to identify and evaluate strategies to mitigate end-of-queue crashes at flagging stations on two-lane roads. The research team evaluated the following treatments based on feasibility and advantages of each treatment: \u2022 Install light-emitting diodes (LEDs) or a warning light on the static BE PREPARED TO STOP (BPTS) sign. \u2022 Switch to a portable changeable message sign (PCMS) in lieu of the static BPTS sign. \u2022 Use a portable traffic signal (PTS) in lieu of the flagger at flagging operations. Researchers collected speed profile data of decelerating vehicles at 18 sites across Texas for the baseline (static BPTS sign) treatment and one or more other treatments. The results did not show any meaningful differences between mean speeds of baseline treatment and the BPTS sign with LED lights, BPTS sign with a warning light, or PCMS. Differences were detected when a PTS was used in lieu of a flagger, but only a limited amount of data was available for analysis. Researchers conducted a benefit-cost analysis, which only included capital costs, operation and routine maintenance costs, and transportation costs, when available. Cost savings of utilizing PTSs in lieu of flaggers were realized in just 2 years. However, more research is needed to determine its effectiveness in reducing end-of-queue crashes at flagger stations

Technical report (Texas Transportation Institute)

Report of a project to identify and evaluate methods that may reduce the number of sign hit by errant vehicles with field studies conducted near Corpus Christi, Texas

Technical report (Texas Transportation Institute)

"This report describes the methodology and results of analyses performed to determine whether the following longitudinal channelizing device (LCD) applications improve the traffic safety and operations of work zones relative to the use of standard drums.

Technical report (Texas Transportation Institute)

"This report provided Texas Department of Transportation (TxDOT) with guidance on developing a well-designed asset management system as a critical component of the agency's approach to providing for the mobility of its customers, preserving the infrastructure already in place, planning for future improvements of that infrastructure, and being responsive and accountable to the public regarding the investment of their tax dollars.