01594582

Component

http://www.trb.org/Main/Blurbs/174123.aspx

Undivided highways consistently perform at low levels of safety, particularly in urban and suburban areas. Between 1999 and 2007, several Louisiana Department of Transportation and Development (DOTD) district offices identified the reduction of rear-end crashes on four-lane undivided highways as an urgent need. To meet this need within the available budgets, the district offices received permission to convert several segments of undivided four-lane roadways into five-lane roadways; the center lane served as a two-way left turn lane. The conversion required restriping the pavement markings without increasing the pavement width. In this research, crash modification factors were identified and developed to determine the effectiveness of Louisiana's restriping projects in reducing crashes or crash severity. Six years of crash data from four restriped highway segments was analyzed to compare the three years before and after restriping. On all four segments overall crash rates were reduced. Benefit cost ratios are also discussed in this article.

English

pp 43-44

2016-1

TR News

Digital/other

Figures; Photos; References; Tables

Before and after studies; Benefit cost analysis; Crash rates; Four lane highways; Highway safety; Multilane highways; Rear end crashes; Suburbs; Urban areas

Louisiana

Highways; Safety and Human Factors

TRIS, TRB, ATRI

Mar 24 2016 4:47PM

• Improving the Reliability and Resiliency of Traffic Signals in an Urban Environment: Cost–Benefits in Washington, D.C.
• NCHRP REPORT: Evolutions in the Geometric Design of Highways and Streets: Integrating Performance-Based Analysis
• NCHRP REPORT: Productivity: The Connection Between Transportation Performance and the Economy
• NCHRP REPORT: Rail Corridor Capacity: Unraveling the Mysteries of Shared Corridor Management
• NCHRP SYNTHESIS REPORT: Responses to Extreme Weather Impacts: Practices in the U.S. Transportation Sector
• POINT OF VIEW: Estimating Preconstruction Costs: Who Cares? Why Bother?
• Reducing Carbon Dioxide Emissions from Daily Travel: Insights from Germany
• Steering the Way Through Disruptions and Transformations: Findings from the Transportation Research Board’s 2015 State Partnership Visits Program