Journal of Transportation Research

Journal of Transportation Research

Development of Spatial and Temporal Speed Relationships in the Capacity of Tehran and Karaj Freeways

Document Type : Original Article

Authors
Amir Hossein Jashnian
Mahdi Tamaddon gohar
Ph.D., Candidate, Faculty of Civil Engineering, Architecture, and Art, Islamic Azad University, Science and Research Branch, Tehran, Iran.
10.22034/tri.2025.499779.3313
Abstract
To ensure safety and optimize traffic management, adherence to spatial and temporal speeds based on native data and highway capacity is essential, particularly when facing sudden deceleration of the leading vehicle. In this study, data recorded by traffic surveillance cameras and the Police Traffic Organization's database from 2021 were collected and analyzed using SPSS software. The research methodology included Pearson correlation analysis and modeling of spatial and temporal speed relationships based on empirical data. The novelty of this study lies in the development of calibrated models based on Iran's local traffic conditions and their comparison with international standards. The results indicated a strong positive relationship between spatial and temporal speeds, where an increase in temporal speed leads to an increase in spatial speed. Additionally, the significance level of the test was zero, confirming the statistical reliability of the findings. These results can be effectively utilized in traffic modeling, freeway capacity optimization, and improving road safety.
Keywords
Spatial Speed Relationships
Time
Freeway Capacity
Tehran and Karaj
Subjects
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