International Journal of Transportation Engineering

International Journal of Transportation Engineering

A Model for Determining Railway Network Capacity (Case Study: Iran Network)

Document Type : Research Paper

Author
Hassan Khaksar
Assistant Professor of Civil Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
10.22119/ijte.2025.487492.1676
Abstract
Capacity of lines and stations is one of the most influential and important factors in network planning and operation. Various methods and methodologies exist for calculating capacity. Accurately and appropriately determining this concept in railway network lines is a very complex task. This becomes even more important when considering the number of network blocks and their different characteristics and properties. In recent years, the Scott method has been used to calculate line capacity. This research aims to identify the various methods of calculating capacity in networks. Furthermore, while comparing these methods, an attempt has been made to introduce a suitable method for use in the country. To this end, by considering the characteristics of the country's railway network and calculating the capacity of 8 selected routes, an attempt has been made to identify a method suitable for the country's railway network. The International Union of Railways (UIC) has presented methods for calculating network capacity under codes 405 and 406. Based on the results of this research, the method presented in the UIC406 guideline, which is the latest and most up-to-date method of this union, has a good fit with the country's network conditions and can be used in the country's railway network. One of the outputs of this study is a software for calculating the capacity of the country's rail network based on UIC code 406. The outputs of this software include train capacity (train set of each block), tonnage capacity in two modes of dominant tonnage and maximum tonnage (nominal tonnage), network bottlenecks based on the performance-to-capacity ratio, and sensitivity analysis of various solutions to increase network capacity.
Keywords
Capacity Analysis
UIC 406
Rail network
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International Journal of Transportation Engineering
Volume 13, Issue 1 - Serial Number 49
Summer 2025
Pages 2067-2079