提高高速公路环路安全水平,通过积极的基于风险的评估使用横向加速的几何配置
Omid Rahmani1, Hosein Ghasemzadeh Tehrani1, Iman Aghayan1
1Faculty of Civil Engineering, Shahrood University of Technology, Shahrood, Iran.
Traffic injury prevention
|September 26, 2024
概括
本研究介绍了循环安全级别 (LSL),以使用横向加速和碰撞数据来评估循环坡道安全性. 这些发现有助于设计人员改进几何配置,以实现更安全的驾驶条件.
科学领域:
- 交通工程是交通工程.
- 道路安全分析 道路安全分析
- 几何设计 几何设计
背景情况:
- 循环坡道存在复杂的几何挑战,因为它结合了水平曲线和垂直对齐.
- 了解循环坡道上的驾驶行为对于将设计假设与现实世界性能对齐至关重要.
研究的目的:
- 调查自由流环坡道的安全性,性能和几何配置.
- 分析驾驶行为和安全水平,以改进设计.
主要方法:
- 利用无人机 (UAV) 数据来分析车辆的行为.
- 使用最大横向加速 (a_y,i) 作为替代安全措施 (SSM).
- 引入了a/b比率和循环安全水平 (LSL) 用于形状确定和风险分析,结合值横向加速度 (a_t) 和第85百分位数最大横向加速度 (a_y,max,85%).
主要成果:
- 基于循环几何学的最大横向加速度的预测模型显示出一个强大的匹配 (R2=0.88).
- 较高的LSL值表明与循环形状和横向加速度相关的安全问题更大.
- 碰撞统计数据与横向加速度数据相关联,以提供安全评级和诊断段安全.
结论:
- 该研究增强了对循环坡道几何配置中的安全考虑的理解.
- 它提供了在设计过程中改进循环的一般形状的见解.
- 开发的LSL有助于积极的风险分析和循环坡道的排名.
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