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Evaluation of Safety in Horizontal Curves of Roads Using a Multi-Body Dynamic Simulation Process
Amir Saman Abdollahzadeh Nasiri1, Omid Rahmani2, Ali Abdi Kordani3
1Department of Civil Engineering, South Tehran Branch, Azad University, Tehran 1584715414, Iran.
Summary
Road safety is enhanced by considering vehicle type and road design, especially on horizontal curves. Simulation results show safety margins decrease with higher speeds and specific grades, highlighting the need for differentiated design standards.
Area of Science:
- Road safety engineering
- Transportation public health
- Vehicle dynamics
Background:
- Road transportation is a significant public health risk, with road safety intricately linked to public health outcomes.
- The geometric design of road infrastructure, particularly horizontal curves, plays a critical role in ensuring road safety and preventing accidents.
- Existing standards, such as those from the American Association of State Highway Transportation Officials (AASHTO), guide the design of horizontal curves.
Purpose of the Study:
- To evaluate the safety aspects of horizontal curves based on AASHTO standards using multi-body dynamic simulation.
- To investigate the influence of various factors, including vehicle characteristics (weight, dimensions), longitudinal grades, and speed, on horizontal curve safety.
- To propose a novel methodology for assessing road safety in the context of horizontal curve design.
Main Methods:
- Multi-body dynamic simulation was employed to analyze the safety of horizontal curves.
- Simulations incorporated various factors: vehicle weight, dimensions, longitudinal grades (upgrades and downgrades), and vehicle speed.
- Analysis focused on lateral friction demand between tire and pavement and a defined safety margin parameter, using simple circular and clothoid curves.
Main Results:
- A significant finding is the need to differentiate design considerations for light versus heavy vehicles, particularly on curves with large radii.
- The safety margin was observed to decrease upon entering a curve, with greater reductions on clothoid curves compared to simple circular curves at lower grades.
- Increasing vehicle speed led to a growing discrepancy between simulated lateral friction demand and AASHTO-proposed values.
Conclusions:
- The study underscores the importance of vehicle-specific design parameters in horizontal curves to enhance road safety.
- Longitudinal grades and curve types (simple circular vs. clothoid) significantly impact safety margins, necessitating careful consideration during design.
- The developed simulation methodology offers a valuable tool for evaluating and improving the safety of road horizontal curves.
Keywords:
accident analysis and preventionhorizontal curvesmobilitymulti-body dynamic simulationpublic health risksroad designroad safetyroad traffic injuriessafety margin parametertraffic safetytransporttransport safetyworld health organizationMore Related Videos
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