Highway Work Zone Capacity Estimation Using Field Data from Kansas, TPF-5(081), 2015

Although extensive research has been conducted on urban freeway capacity estimation methods, minimal research has been carried out for rural highway sections, especially sections within work zones. This study attempted to fill that void for rural highways in Kansas, by estimating capacity of rural highway work zones in Kansas. Six work zone locations were selected for data collection and further analysis. An average of six days’ worth of field data was collected, from mid-October 2013 to late November 2013, at each of these work zone sites. Two capacity estimation methods were utilized, including the Maximum Observed 15-minute Flow Rate Method and the Platooning Method divided into 15-minute intervals. The Maximum Observed 15-minute Flow Rate Method provided an average capacity of 1469 passenger cars per hour per lane (pcphpl) with a standard deviation of 141 pcphpl, while the Platooning Method provided a maximum average capacity of 1195 pcphpl and a standard deviation of 28 pcphpl. Based on observed data and analysis carried out in this study, the suggested maximum capacity can be considered as 1500 pcphpl when designing work zones for rural highways in Kansas. This proposed standard value of rural highway work zone capacity could be utilized by engineers and planners so that they can effectively mitigate congestion at or near work zones that would have otherwise occurred due to construction/maintenance.

Corridor Management Pilot Projects, 2004

Managing existing and newly constructed highway corridors has recently become a significant concern in many states, including Iowa. As urban land and land on the urban fringe develops, there is pressure to add features such as commercial driveways, at-grade public road intersections, and traffic signals to arterial highway routes that should primarily serve high-speed traffic. This diminishes the speed and traffic capacity of such roadways and can also cause significant safety issues. if mobility and safety are diminished, the value of the highway investment is diminished. Since a major highway corridor improvement may cost tens of millions of dollars or more, corridor management is as critical to preserving that investment as is more "hard side" management practices such as pavement or bridge management. Corridor management is a process that applies access management principles to highway corridors in an attempt to balance the competing needs of traffic service, safety, and support for land development. This project helped to identify routes that should be given high priority for corridor management. The pilot study in the form of two corridor management case studies provides an analytical process that can be replicated along the other Iowa commuting corridors using commonly available transportation and land use data resources. It also offers a general set of guidelines for the Iowa Department of Transportation to use in the development of its own comprehensive corridor management program.

Traffic Management Strategies for Merge Area in Rural Interstate Work Zones, CTRE 97-12, 1999

The Iowa Department of Transportation, like many other state transportation agencies, is experiencing growing congestion and traffic delays in work zones on rural interstate highways. The congestion results in unproductive and wasteful delays for both motorists and commercial vehicles. It also results in hazardous conditions where vehicle stopped in queues on rural interstate highways are being approached by vehicles upstream at very high speeds. The delays also result in driver frustration, making some drivers willing to take unsafe risks in an effort to bypass delays. To reduce the safety hazards and unproductive delays of congested rural interstate work zones, the Iowa Department of Transportation would like to improve its traffic management strategies at these locations. Applying better management practices requires knowledge of the traffic flow properties and driver behavior in and around work zones, and knowledge of possible management strategies. The project reported here and in a companion report documents research which seeks to better understand traffic flow behavior at rural interstate highway work zones and to estimate the traffic carrying capacity of work zone lane closures. In addition, this document also reports on technology available to better manage traffic in and around work zones.