Original scientific paper
https://doi.org/10.7307/ptt.v29i2.2041
Incorporating Traffic Control and Safety Hardware Performance Functions into Risk-based Highway Safety Analysis
Zongzhi Li
Hoang Dao
; Illinois Institute of Technology
Harshingar Patel
; Illinois Institute of Technology
Yi Liu
; Wuhan University of Technology
Bei Zhou
; Chang'an University
Abstract
Traffic control and safety hardware such as traffic signs, lighting, signals, pavement markings, guardrails, barriers, and crash cushions form an important and inseparable part of highway infrastructure affecting safety performance. Significant progress has been made in recent decades to develop safety performance functions and crash modification factors for site-specific crash predictions. However, the existing models and methods lack rigorous treatments of safety impacts of time-deteriorating conditions of traffic control and safety hardware. This study introduces a refined method for computing the Safety Index (SI) as a means of crash predictions for a highway segment that incorporates traffic control and safety hardware performance functions into the analysis. The proposed method is applied in a computation experiment using five-year data on nearly two hundred rural and urban highway segments. The root-mean square error (RMSE), Chi-square, Spearman’s rank correlation, and Mann-Whitney U tests are employed for validation.
Keywords
traffic control; safety hardware; safety performance function; highway safety; risk analysis
Hrčak ID:
181720
URI
Publication date:
19.4.2017.
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