Highlights We develop the crash modification factor for changing lane width on roadway segments based on non-linear relationships between lane width and crash rate. We apply the generalized nonlinear model to predict crash frequency in a function of lane width and calculate the crash modification factor based on the model parameter associated with lane width. There were significant effects of interaction between lane width and speed limit on crash frequency. Lane width less than 12ft is more effective in reducing total crashes for the roadway segments with the speed limits higher than or equal to 40mph. Lane width greater than or less than 12ft is more effective in reducing crashes at higher severity levels (KABC and KAB) than total crashes.

    Abstract This study evaluates the effectiveness of changing lane width in reducing crashes on roadway segments. To consider nonlinear relationships between crash rate and lane width, the study develops generalized nonlinear models (GNMs) using 3-years crash records and road geometry data collected for all roadway segments in Florida. The study also estimates various crash modification factors (CMFs) for different ranges of lane width based on the results of the GNMs. It was found that the crash rate was highest for 12-ft lane and lower for the lane width less than or greater than 12ft. GNMs can extrapolate this nonlinear continuous effect of lane width and estimate the CMFs for any lane width, not only selected lane widths, unlike generalized linear models (GLMs) with categorical variables. The CMFs estimated using GNMs reflect that crashes are less likely to occur for narrower lanes if the lane width is less than 12ft whereas crashes are less likely to occur for wider lanes if the lane width is greater than 12ft. However, these effects varied with the posted speed limits as the effect of interaction between lane width and speed limit was significant. The estimated CMFs show that crashes are less likely to occur for lane widths less than 12ft than the lane widths greater than 12ft if the speed limit is higher than or equal to 40mph. It was also found from the CMFs that crashes at higher severity levels (KABC and KAB) are less likely to occur for lane widths greater or less than 12ft compared to 12-ft lane. The study demonstrates that the CMFs estimated using GNMs clearly reflect variations in crashes with lane width, which cannot be captured by the CMFs estimated using GLMs. Thus, it is recommended that if the relationship between crash rate and lane width is nonlinear, the CMFs are estimated using GNMs.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Development of crash modification factors for changing lane width on roadway segments using generalized nonlinear models


    Beteiligte:
    Lee, Chris (Autor:in) / Abdel-Aty, Mohamed (Autor:in) / Park, Juneyoung (Autor:in) / Wang, Jung-Han (Autor:in)

    Erschienen in:

    Erscheinungsdatum :

    2015-01-08


    Format / Umfang :

    9 pages




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Elektronische Ressource


    Sprache :

    Englisch