This paper addresses priced managed lane corridors, on which travelers may choose to pay a toll to travel on the managed lanes (MLs) to realize generally faster, more reliable travel than on the adjacent, toll-free general purpose lanes (GPLs). These lanes exist in many cities across the United States and are becoming more common as transportation agencies look for innovative ways to increase capacity and regulate demand for their roadways. Commonly, demand for these lanes is modeled assuming travelers choose between the MLs and GPLs primarily based on the cost and time savings of the MLs. Although the traffic and revenue forecasts generated by these models have generally succeeded in estimating revenue, newly available empirical data from Katy Freeway and North Tarrant Express shows these models fail to capture how individual drivers make decisions. Most travelers on those freeways were not choosing—they always used the same lane regardless of travel time and toll. Travelers that used both sets of lanes often made choices that appeared counter-intuitive based on travel time savings and toll rate. This research provides a preliminary investigation into this issue, which calls into question all prior ML travel-behavior research.

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Growing awareness of environmental and public health problems associated with motorized transportation has led to a recent effort to promote nonmotorized modes of travel. Previous studies have shown that facility design plays a large role in encouraging bicycling. With the aim of defining the roadway configurations that lead to safe motorist and bicyclist behavior, this research examines the impact of design elements, including the type and width of the bicycle facility, the presence of adjacent motor vehicle traffic, parking turnover rate, land use, and the type of motorist-bicyclist interaction. Observational studies conducted at 48 sites in three large Texas cities characterize bicyclist and motorist behavior through lateral position measurements and instances of motorist encroachment on an adjacent lane. These observations were used to build two multivariate regression models and allowed for direct site-to-site comparisons. Notable results include the observation that bicycle lanes create a safer and more predictable riding environment relative to wide outside lanes, and that the provision of a buffer between parked cars and bicycle lanes is the only reliable method for ensuring that bicyclists do not put themselves at risk of being hit by opening car doors.

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