Left-turn lanes are commonly used to provide space to accommodate vehicle deceleration and provide adequate storage of turning vehicles. The objective of this study is to evaluate the safety effectiveness of extending the length of left-turn lanes at signalized intersection approaches. Five years of collision data including injury severity and collision type from three treatment sites and 31 comparison sites in the City of Surrey, Canada were used in the study. The analysis focused on target crashes including left-turn-related rear-end and left-turn-related sideswipe collisions. A full Bayesian (FB) before–after analysis was conducted for all collisions, severity levels, and collision types. Multivariate Poisson–lognormal linear intervention models were used for the analysis. The treatment effectiveness index was calculated to quantitatively measure the effectiveness of the safety treatment. The FB before–after results showed that the treatment-related collisions were reduced by 57.4% following the implementation of extended left-turn lane. The reduction in injuries and fatalities collisions (63.8%) was greater than that in property damage only collisions (55.7%). The decrease in rear-end collisions (62.8%) was greater than that in sideswipe collisions (58.1%). The findings indicate a remarkable improvement in safety after the length extension of the left-turn lane.


    Access

    Download

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Before–After Evaluation of Left-Turn Lane Extension Considering Injury Severity and Collision Type


    Additional title:

    Transportation Research Record: Journal of the Transportation Research Board


    Contributors:
    Guo, Yanyong (author) / Sayed, Tarek (author)


    Publication date :

    2020-05-05




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English



    Collision Experience at Dual-left-turn Lane versus Single-left-turn Lane Permissive and Exclusive Operation

    Basha, P.E. / Institute of Transportation Engineers | British Library Conference Proceedings | 2010


    Injury and Collision Severity

    Mackay, G. Murray | SAE Technical Papers | 1968


    Injury and collision severity

    Mackay, G.M. | Engineering Index Backfile | 1968


    Left-Turn Lane Design and Operation

    L. Yu / Y. Qi / M. Azimi et al. | NTIS | 2008


    A comparison of collision-based and conflict-based safety evaluation of left-turn bay extension

    Guo, Yanyong / Zheng, Lai / Sayed, Tarek | Taylor & Francis Verlag | 2020