Upgrading of the rail vehicles is in line with the policies of the Iran's twenty-year development vision document (Horizon 1404) in order to increase the share of railways in the transportation of goods up to 30%. The design of freight wagons with higher axial load, provides the possibility of increasing the load carrying capacity of the wagons, helps to achieve environmental goals through less CO2 emission, and causes a significant reduction in the transportation cost, which itself leads to more investment by the private sector in the Iran's rail vehicles. This paper presents a computational platform to analyze the mechanical strength of a long-sided freight wagon with an axle load of 25 tons, according to the requirements of EN 12663-2 standard, using the finite element method. Design requirements are described in detail and appropriate numerical models are developed for each requirement. The results of the simulations performed in all loading conditions have been compared with the limits defined in the standard and the correctness of the design has been ensured. Numerical results depict that among all load cases, lifting at one end, lifting the whole vehicle (load cases LC6 and LC7) and compressive force and vertical load (load case LC8) cases are the most sever ones, and induce higher local stresses; which could be reduced by reinforcing or making some geometrical changes in the underframe. In general, the outputs of this research will help the railways engineers to identify and optimize the high stress regions of the freight wagon underframe, under different loading conditions. Such modifications, not only optimize the weight and increase the strength and the load carrying capacity of the wagon, but also increase its useful life time and operational reliability.

Productivity is an important issue in Key Performance Indicators of Rail Transportation. Comparison shows that Freight Wagon Productivity is less than Pioneer countries. It is possible to multiple it in future years gradually. With Increase in Freight Wagon Productivity, Rail Freight Share and Attraction of Investment will be increased and National Economy uses its considerable benefits. With Review of Previous Studies, Suggested Method for Analyzing of Freight Wagon Productivity with unit of “, Speed”,is proposed in National Level. Status of Freight Wagon Productivity has reviewed for last years in National and Corporate Level. For Next Future 20 Years, Quantitative Goals in 4 Program of 5 Years is proposed mainly according to increase of existing asset Productivity. Because mentioned Indicator is important in Rail Freight Productivity and increase of it can show a kind of progress in Productivity of human resources, Rail Infrastructure and even Diesel Locomotives, and because of Simplicity and Not Complexity in Supervision by Related Authorization Organizations, it Suggests that in First Step it establish and pass and submit by National Parliament with respect to specified method explained in this article and Specific Quantities Goals. It can be used for interaction of Parliament with Transportation Minister and also Transportation Minister can be using it in interaction with Managing Board of Iranian Railway State Co. (RAI).

This paper presents the design and development of a hybrid power supply system for freight railway wagons, aiming to enhance energy autonomy and reduce maintenance requirements. The system utilizes solar energy and rechargeable batteries as primary power sources. An ESP32 microcontroller serves as the central unit, managing energy resources, battery charging and discharging processes, and protecting the connected loads. Additionally, the design includes voltage regulation circuits, current protection mechanisms, and voltage and current sensing modules to ensure precise monitoring and stable operation of the system. Simulation and experimental results confirm the high reliability of the system under various operating conditions and its ability to provide continuous power to the wagon's onboard loads.

Public transportation has always been of great interest to researchers and has been considered an essential and efficient method for transporting people and various goods over the past two centuries. In recent studies, the examination of influential parameters on the efficiency of these vehicles has played a prominent role, and numerous researchers have continuously investigated the safety and various parameters of freight wagons. One of the challenges that can be raised as an issue in standard open-top freight wagons is the placement and positioning of the load inside these wagons. Considering that loading these wagons is not standardized in the industry and the load may be placed more or less in different positions at each loading stage, examining the effect of this issue on the safety of the movement of wagons in a curve can be essential. In this study, by considering a standard open-top freight wagon in the Universal Mechanism software, the effect of placing a hypothetical concentrated load in four different positions on the derailment coefficient in a curve with three different non-critical speeds is investigated. Ultimately, by comparing the results, the effect of this parameter on the derailment coefficient is discussed. The focus of this study was solely on the safety of the wagon's movement.

As railroad is responsible for a major share of freight transportation compare with other in-land transportation modes, appropriate grouping and scheduling of the freight wagons can lead to significant decrease in emissions exhausted by diesel locomotives. In this study, we evaluated the impact of different freight wagon grouping and scheduling policies by simulating moving trains on Iran’ s railroad network. The simulated model is accounting for scheduling, classification and train formation simultaneously. To consider the variation of demand for freight transportation of Iran’ s railroad network according to different grouping and scheduling policies, eight scenarios designed in addition to do-nothing. Therefore, the values of main pollutant including? CO? _2,? SO? _2, PM,? NO? _x, CO and HC emissions are calculated for each scenario by simulation. Results show that simultaneous implementation of non-necessary grouping policy and flexible scheduling policy can lead to lower amount of total emissions. The conclusion provide useful suggestion on grouping policy for Iran railroad network.

This article compares the characteristics of the improved bogie used in the long-edge mineral freight car to bear the axial load of 22.5 tons with the original H665 bogie. The H665 bogie is being used in the Middle East and specifically in the cargo fleet of Iran. Static and vibration analysis of individual parts and the infrastructure of railway vehicles is an integral part of designing and improving the performance of railway vehicles. Therefore, static and vibration analysis of the bogie frame was performed in our model using the finite element method. The Abaqus software package performed numerical calculations based on the FEM approach. In this research, theoretical results related to structural stress values , natural frequencies, and shape of vibration modes of the improved bogie and the original bogie were extracted. While comparing the results, the amount of structural stress reduction and the feasibility of increasing this axial load were investigated.

Rail profile irregularities are one of the main vibration sources to vehicle and track. In this paper derailment of a wagon moving on cable-stayed bridge due to rail irregularities is investigated. The four-axle wagon model is a three-dimensional, non-linear model of a train freight car with 38 DOF. Two parallel rails of the track are modeled as Euler-Bernoulli beams on elastic points as rail pads. The bridge deck is modeled as a plate supported by some cables. Using this model; the effects of wagon specifications, lateral position of the rails and rail irregularities on wagon derailment have been studied.

Managers and transportation planners have always paid special attention to rail transport and its development due to its high capacity and low shipping costs. In general, two solutions apply to the development of rail transit 1. deployment of new infrastructure and 2. improvement of existing conditions and procedures, which the second approach associated with a lower cost. This study proposes a dynamic binary mathematical programming model to formulate the existing rail freight procedures. Unlike previous studies, this paper uses a dynamic binary variable to express the wagon state (origin, destination, full or empty, and so on). Also, the current study proposes two simulation scenarios (FCFS: First Come First Served and SPT: Shortest Processing Time) for solving mathematical programming. In this paper, two different perspectives are considered 1. maximize the railway of the Islamic Republic of Iran (RAI) revenue and 2. maximize the rail transport companies' benefit. The main constraints are the loading /unloading capacity of stations, rail line capacity, and the capacity of locomotives to make up trains. Also, this study assumes that freight demand, travel time, and unloading /loading time are stochastic variables. In summary, this paper argued that the SPT strategy requires fewer wagons than FCFS, while the average productivity in SPT mode increases approximately by one unit, and unmet demand decreases. The results also show that the revenue of the rail freight companies in SPT strategy is more than FCFS strategy in all scenarios. Finally, based on the proposed model, it is determined that the service in the SPT strategy has better conditions than the FCFS strategy. The results of the models based on both views of RAI and rail freight companies indicate that all indicators' performance is similar. Comparing the results of the models with/without taking wagons maintenance into account shows that if the maintenance of wagons is considered, the numbers of required wagons will increase, productivity will decrease, average revenue per wagon of RAI and the average profit of rail freight transport companies will reduce.

The factors used in the foresight of any system vary from country to country, society, culture, politics and even time. Identifying and planning for influential factors in any industry is of particular importance. By identifying influential indicators, planners and policymakers determine which indicators are prioritized. Also, to move towards the main goal of organizations, identifying these indicators will help policymakers and planners to invest and optimize the most important indicators.The main purpose of this study is to identify the political factors affecting the future of the rail transport system in the freight sector. In this research, the identification of political factors of the rail transportation system in the freight sector has been done using a combination of library, field and Delphi studies and Micmac software has been used in the analysis. The three stages of this research have sought to present the most important political factors affecting the future of rail transportation in Iran. In the first step, all factors were identified. In the second stage, using the Delphi method, a consensus was reached in three consecutive periods, and in the third stage, using Micmac software, eleven factors in three categories were presented as the most important drivers for the future of the rail freight transportation system. .