Impact of Pavement and Weather Conditions on Traffic Speed at Sharp Horizontal Curves

Lane departure crashes on sharp horizontal curves are a major safety concern on both highways and freeways, accounting for a disproportionately high number of fatal and severe injury crashes. Research has shown that these crashes are often linked to speeds relative to curve geometry. While geometric design factors like curve radius and superelevation have been well studied, less attention has been given to how pavement and weather conditions influence traffic speed on these elements. Particularly, current safety models do not fully account for the effects of pavement surface conditions, such as friction, roughness, and texture, or adverse weather elements like precipitation, temperature drops, and reduced visibility. While the impact of factors like road curvature effects on traffic speed have been studied, current models often fail to integrate the complex interaction of pavement conditions and weather data in predicting traffic speeds. This results in inaccurate speed predictions, which can compromise safety and infrastructure planning. Without comprehensive, data-driven models, interventions such as speed limits, signage, or road maintenance are often poorly targeted, leading to higher risks of crashes, congestion, and inefficient resource allocation. The motivation for this project is to develop a predictive model that integrates pavement conditions, weather effects, and road geometry to estimate traffic speed at horizontal curves. This will provide safer roads by enabling better traffic management, targeted infrastructure improvements, and more efficient interventions.

• Record URL:
  • https://www.sptc.org/cy3-osu-ou-02

Language

• English

Project

• Status: Active
• Funding: $224,718.00
• Contract Numbers:

  69A3552348306 (CY3-OSU-OU-02)

• Sponsor Organizations:

  South Dakota Department of Transportation

  700 East Broadway Avenue
  Pierre, SD  United States  57501

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590
• Managing Organizations:

  University of Oklahoma, Norman

  School of Civil Engineering and Environmental Science
  202 West Boyd Street, Room 334
  Norman, OK  United States  73019
• Project Managers:

  Ghasemi, Hamid

• Performing Organizations:

  University of Oklahoma, Norman

  School of Civil Engineering and Environmental Science
  202 West Boyd Street, Room 334
  Norman, OK  United States  73019

  Oklahoma State University, Stillwater

  School of Civil & Environmental Engineering
  Stillwater, OK  United States  74078
• Principal Investigators:

  Li, Joshua

  Shirazi, Ali

• Start Date: 20260101
• Expected Completion Date: 20270101
• Actual Completion Date: 0
• USDOT Program: UTC

Subject/Index Terms

• TRT Terms: Highway curves; Highway safety; Pavement condition; Predictive models; Texture; Traffic speed; Weather conditions
• Subject Areas: Highways; Pavements; Planning and Forecasting; Safety and Human Factors;

Filing Info

• Accession Number: 01975691
• Record Type: Research project
• Source Agency: Southern Plains Transportation Center
• Contract Numbers: 69A3552348306 (CY3-OSU-OU-02)
• Files: UTC, RIP
• Created Date: Jan 5 2026 11:07PM