جستجوی مقالات مرتبط با کلیدواژه "مخاطره" در نشریات گروه "عمران"

Network Transportation Roads as the most widespread and easy access methods of passenger and goods Displacement are Exposure to different kind of disasters. On the one hand, Variety and Expansion of disasters due to Geographical situation of Iran and on the other hand Depreciation of Transportation Infrastructures, because the daily increase of Transportation networks Costs. So, identifying and prioritizing of disaster talented points in this network has an important role in control and decrease the Costs of disasters in suburban Transportation networks. In this research, According to the method which is based on Principles of Engineering Economics, will be paid to Evaluation of disaster costs in Isfahan suburban roads, identification and prioritize of disaster talented points. For example, using this method in Isfahan urban networks create these In Isfahan, 62.6 % of damages in road networks is related to natural hazards and 37.4 % is related to human ones (accidents). Kashan, Shahreza and Shahinshahr & Meimeh are the most risky counties in Isfahan. In Isfahan urban transportation network, Land slide is 10.6 more risky than earthquake and it is 39.3 more risky than flood. If flood in Shoor river damage to Shoor Bridge in Mobarakeh-Boroojen Road, all relations to Semirom County will be broken up. As it shown, this method because of its Ability to consider all natural and human-made disasters simultaneously and also because of its ability to correct the benefit Ratio in each point according to network has the satisfactory answers for Governmental decisions.

This paper is about a risk assessment based approach, for the purpose of evaluating safety performance of the Iran railway industry in some known fire risk areas in a passenger train. The importance of fire investigation is totally due to the railway industry’s authority to control fire related elements and prevent such fire related incidents and accidents by implementing a proper planning and systematic education or at least reducing the damages to the passengers and their financial consequences. According to %25 increase in the fire rate during the period 1997-1999 and %11 reduction in the total rail accidents rate, the importance of fire risk assessment would be increased. Fuzzy FMEA based Grey theory analysis is used for fire risk analysis in three main parts of the railway industry, namely power and air conditioning of passenger wagons, generator and steam. The goal of this methodology are fire hazard detection and diagnosis to determine their causes, the occurrence rate and the severity of the hazard consequences qualitatively, computing the risk value of each failure in its specific subset and analyze the current fire related gaps in the railway industry. Providing a comprehensive data log of all fire mishap reports, would be a useful tool to develop quantitative hazard analysis and risk assessment approaches to improve the current qualitative risk evaluation method in the near future, for the purpose of safety and prevention of fire hazard and its consequences.

Safety is one of the most important issues of transportation systems, and new technologies and complex systems increased the need for a systematic approach. Safety matters have a vital influence on railway transportation, and interacting of factors such as manpower, electric and electronic devices, mechanical faces of locomotives and trains, civil engineering issues in the infrastructure, etc. all make a framework of uncertainty. Level crossing, the most dangerous place of the railway system, has a more complex condition, because it is covered by different type of people: The employees and the public. The second group makes it much more complex, because the factor is out of railway authorities control and they really face to the danger. As it clearly could be understood, assessing safety in this situation is a real hard work, because it is needed to manage issues with different roots in a single framework and synchronization of these factors is not a simple work. This introduction implies the necessity and importance of a criteria and framework which could manage the safety issues in such different faces.Risk, as a simple, easy to understand, strong and adequate criteria, could help us to assess safety issues in different places with a single method. Risk has a double hinges those shown undesirable event happens with witch frequency and witch severity. Therefore, in this research risk was selected as a decision criteria and a framework of tolerable rates was fitted to it. The tolerable rates show risk according witch conditions will be accepted or denied. Lack of national framework for this subject forced research team to determine a local framework for RAI.The second phase of research was designing and generating set of steps and diagrams which as a chain leads to assess the risks in the scope of study. The first step of the process, hazard identification in fact is a process of identifying, predetermining of frequency and severity, and rating at end separating the high rated hazards for further studies. The second phase of this process is causal analysis that includes recognizing roots of the hazard, deceiving their frequency of happiness, determining the chain of their relationship, and at end assessing the hazard occurrence likelihood. Consequence analysis, the third phase of research, is modeling and determining the scenarios which will be happened if the hazard really occurred. The output of this phase is set of consequences and their possibilities ratio. Now is the time for assessing the estimated loss in each kind of scenarios and aggregating them with regards to their possibility ratios which are assessed in the 3rd. phase. At the end of this phase, the risk is assessed and should be compared with tolerable rates. If it is not acceptable, risk mitigation process should be applied. Risk mitigation process will be used for unacceptable risks and its purpose is reducing or eliminating risk sources or decreasing their undesirable consequences. This phase includes two main steps: Option analysis and impact analysis. Option analysis with getting help from innovative methods tries to find a new solutions and methods and its output is the list of options. The impact analysis phase tries to select the best option according to the criteria of risk reduction and cost analysis.Appling the process in Garmdarreh_Level Crossing exhibited that risk could easily demonstrate the safety state of a system and also it showed how modeling and generating causal and consequence charts can help researchers to more easily and more reliable find a solutions and options for reducing risks. The application also shows that the process capability completely covers all the hazards in the scope.