Exploring Safety Impacts of the Number and Arrangement of Lanes on Freeway Entrance Ramps

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Conference Proceeding

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The number and arrangement of lanes on freeway entrance ramps are an important aspect of freeway geometric design. The primary objective of this paper is to explore the impacts of the number and arrangement of lanes on freeway entrance ramps on the safety performance of freeway merging areas. Four different types of entrance ramps were considered. Type 1 and type 2 are one-lane entrance ramps while type 3 and type 4 are two-lane entrance ramps. Cross-sectional comparison was conducted for comparing crash frequency and crash severity between different types of freeway entrance ramps. A combined crash prediction model was developed to identify the different factors that contribute to the crashes reported at selected freeway segments. Based upon the model, replacing a type 1 with a type 2 will result in 63.18% more total crashes. Replacing a type 4 with a type 3 will increase total crashes by 8.84%.

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Citation / Publisher Attribution

CICTP 2017 : Transportation Reform and Change—Equity, Inclusiveness, Sharing, and Innovation, p. 4466-4474