Clear zone or W-beam guardrail for rural highways? A Full Bayes before-after evaluation by employing the Poisson Gamma-Lindley model

IF 6.2 1区工程技术 Q1 ERGONOMICS

Accident; analysis and prevention Pub Date : 2025-09-03 DOI:10.1016/j.aap.2025.108218

Shinthia Azmeri Khan, Hassan Bin Tahir, Shamsunnahar Yasmin, Shimul Md Mazharul Haque

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引用次数: 0

Abstract

Run-off-road crashes often result in fatal and severe injuries on rural highways. Clear zones and W-beam guardrails are often installed to reduce run-off-road crashes and the extent of severe injuries. While the effectiveness of clear zone improvement and W-beams has been studied, their comparative effects in a similar empirical setting are not well known. At the same time, crashes on rural highways are often characterized by a high frequency of zero counts; however, models capable of addressing this issue—such as the Poisson-Gamma Lindley models—have not yet been tested in before-after evaluations of engineering treatments. Towards this end, this study aims to examine the safety effectiveness of clear zones and W-beam guardrails on rural highways by applying a Full Bayes approach with Poisson-Gamma Lindley model that considers heterogeneities resulting from the preponderance of zeros. A total of 82.70 km of treated roadway segments with Clear zone improvements (0–5 m to 5–10 m) implemented in 2014 and 2015 were extracted from Bruce Highway in Queensland, Australia. W-beam guardrails were installed along a total of 45.5 km of the same rural highway between 2013 and 2017. The computed Crash Modification Factors (CMFs) show that the clear zone widening significantly reduced total injury (CMF = 0.57), fatal, serious, and moderate injury (CMF = 0.58), fatal and serious injury (CMF = 0.53), and run-off-road crashes (CMF = 0.63). W-beam guardrails are also found to significantly reduce total injury (CMF = 0.75), fatal, serious, and moderate injury (CMF = 0.77), fatal and serious injury (CMF = 0.81), and run-off-road crashes (CMF = 0.56). Overall, both countermeasures significantly reduce run-off-road crashes and other injury severities, including total injury, fatal, serious, and moderate injury, and fatal and serious injury crashes. W-beam guardrails have been found to provide greater reductions in run-off-road crash occurrences, whereas clear zone improvements are more effective in reducing injury severity by offering more forgiving roadside conditions.

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在乡村公路上设置透明区或w梁护栏？采用泊松-伽玛-林德利模型进行了全贝叶斯前后评价

农村高速公路上的越野车事故经常造成严重伤亡。通常会安装透明区和w梁护栏，以减少越野车碰撞和严重伤害的程度。虽然已经研究了透明区改进和w光束的有效性，但在类似的经验设置中，它们的比较效果尚不清楚。与此同时，农村高速公路上的撞车事故往往以高频率的零计数为特征；然而，能够解决这个问题的模型，如泊松-伽玛林德利模型，尚未在工程处理的前后评估中进行测试。为此，本研究旨在通过应用考虑零优势导致的异质性的泊松-伽玛林德利模型的全贝叶斯方法来检验农村高速公路上透明区和w梁护栏的安全有效性。从澳大利亚昆士兰州的布鲁斯高速公路上提取了2014年和2015年实施的82.70公里的经过处理的路段，并进行了清晰区改进（0-5米至5-10米）。2013年至2017年期间，同一条农村公路上总共安装了45.5公里的w梁护栏。计算的碰撞修正因子（CMF）表明，明确区域的扩大显著降低了总伤害（CMF = 0.57）、致命、严重和中度伤害（CMF = 0.58）、致命和严重伤害（CMF = 0.53）和越野车碰撞（CMF = 0.63）。w梁护栏还能显著降低总伤害（CMF = 0.75），致命、严重和中度伤害（CMF = 0.77），致命和严重伤害（CMF = 0.81），以及越野车碰撞（CMF = 0.56）。总体而言，这两种对策都显著减少了越野跑事故和其他伤害严重程度，包括总伤害、致命、严重和中度伤害以及致命和严重伤害事故。研究发现，w梁护栏可以更有效地减少越野车事故的发生，而通过提供更宽松的路边条件，改进透明区域可以更有效地降低伤害严重程度。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Accident; analysis and prevention Multiple-

CiteScore

11.90

自引率

16.90%

发文量

264

审稿时长

48 days

期刊介绍： Accident Analysis & Prevention provides wide coverage of the general areas relating to accidental injury and damage, including the pre-injury and immediate post-injury phases. Published papers deal with medical, legal, economic, educational, behavioral, theoretical or empirical aspects of transportation accidents, as well as with accidents at other sites. Selected topics within the scope of the Journal may include: studies of human, environmental and vehicular factors influencing the occurrence, type and severity of accidents and injury; the design, implementation and evaluation of countermeasures; biomechanics of impact and human tolerance limits to injury; modelling and statistical analysis of accident data; policy, planning and decision-making in safety.