The Effects of Speed and Flow Characteristics on Crash Rates for Wasit Multi-lane Highways in Iraq


  • Amjad H. Albayati Department of Civil Engineering, University of Baghdad, Baghdad, Iraq
  • Zahraa A. Ramadan Department of Civil Engineering, University of Baghdad, Baghdad, Iraq



Traffic safety, crash rates, multilane highways, average spot speed, hourly traffic volume, multiple regression.


This study describes traffic crash rates in selected multilane rural highways in Wasit governorate in Iraq. The main objective of this research is to investigate relationships between total, fatal crash rates and their kinds and factors such as hourly traffic flow and average spot speed.

The study is based on data collected from two sources: police stations and traffic surveys. Three highways are selected to cover the locations of the accidents. The selection includes Kut – Suwera with five segments, Kut – ShekhSaad with three segments, and Kut – Hay with two segments multilane divided highways.

Multiple linear regression analysis is applied to the data by using SPSS software to attain the relationships between the dependent variables and the independent variables in order to identify elements that are strongly correlated with crashes rates and severity.

Seven regression models are developed which verify weak and strong statistical relationships between crashes types and average spot speed with hourly traffic flow respectively. As the hourly traffic flow of automobile grows, the need for safe traffic facilities also grown.



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How to Cite

H. Albayati , A. ., & A. Ramadan , Z. . (2021). The Effects of Speed and Flow Characteristics on Crash Rates for Wasit Multi-lane Highways in Iraq. Wasit Journal of Engineering Sciences, 9(1), 22–36.