Understanding the Contributing Factors to Nighttime Crashes at Freeway Mainline Segments

Hongyun Chen,Kristiansson Fanny

doi:10.4236/jtts.2019.94028

Hongyun Chen, Kristiansson Fanny

Open Access

https://doi.org/10.4236/jtts.2019.94028

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Abstract

This study investigated the crash contributing factors to the injury outcomes and the characteristics of the night time crashes at freeway mainline segments. Multinomial logit model (MNL) was selected to estimate the explanatory variables at a 95% confidence level. The six-year crash data (2005-2010) were obtained in the State of Florida, USA and five injury level outcomes, no injury, possible injury, non-incapacitating injury, capacitating injury, and fatal injury, were considered. The no injury level was selected as the baseline category.

Highlights

Driving during nighttime tends to be riskier than day time [1]
This study investigated the crash contributing factors to the injury outcomes and the characteristics of the night time crashes at freeway mainline segments
The purpose of this study is to investigate the crash contributing factors to the injury outcomes and the characteristics of the night time crashes at freeway mainline segments

Summary

Introduction

Driving during nighttime tends to be riskier than day time [1]. Though vehicles travelling at night is about 25 percent of the total traffic, the nighttime crash rate remains high in the past decades, in general approximately 1.6 times of the daytime rate [2]. A study conducted by Griffith [4] compared the night time crashes on a 55-mile long urban freeway segment with continuous lighting and a 36 mile without lighting. It only found the significant difference for PDO crash rates, which is 19 percent higher at those without street lighting. These studies were conducted about 15 to 20 years ago while the sample sizes were limited, and detailed levels of crash information might not be available at that time which could significantly lead to the bias in the estimation. The findings from this study could help the engineers and researchers to further select the effective countermeasures or policies to effectively reduce the night time crashes, especially the injury severity levels

Methology

Data Collection

Data Analysis

Findings

Conclusions