Embedding the human factor in road tunnel risk analysis (original) (raw)

Enhancing Road Tunnel Risk Assessment with a Fuzzy System Based on the Cream Methodology

Chemical engineering transactions, 2013

Konstantinos Kazaras*, Myrto Konstandinidou, Zoe Nivolianitou, Konstantinos Kirytopoulos National Technical University of Athens, School of Mechanical Engineering, Heroon Polytechniou 9, Zografou campus, 15780, Greece. Systems Reliability and Industrial Safety Laboratory, Institute of Nuclear & Radiology Sciences & Tecnology, Energy & Safety, National Center for Scientific Research “Dimokritos”, Aghia Paraskevi 15310, Greece. kkaz@central.ntua.gr

RISK ANALYSIS METHODOLOGY FOR ROAD TUNNELS AND ALTERNATIVE ROUTES

2000

The work includes an overview of road tunnel risk analysis methodologies that have been developed in Europe as a consequence of several major accidents and subsequent Directive on minimum safety requirements for road tunnels. In our analysis, we used PIARC - OECD quantitative risk assessment model (QRAM), which includes the largest choice of different scenarios, tunnel types and traffic parameters.

Introducing the STAMP method in road tunnel safety assessment

Safety Science, 2012

After the tremendous accidents in European road tunnels over the past decade, many risk assessment methods have been proposed worldwide, most of them based on Quantitative Risk Assessment (QRA). Although QRAs are helpful to address physical aspects and facilities of tunnels, current approaches in the road tunnel field have limitations to model organizational aspects, software behavior and the adaptation of the tunnel system over time. This paper reviews the aforementioned limitations and highlights the need to enhance the safety assessment process of these critical infrastructures with a complementary approach that links the organizational factors to the operational and technical issues, analyze software behavior and models the dynamics of the tunnel system. To achieve this objective, this paper examines the scope for introducing a safety assessment method which is based on the systems thinking paradigm and draws upon the STAMP model. The method proposed is demonstrated through a case study of a tunnel ventilation system and the results show that it has the potential to identify scenarios that encompass both the technical system and the organizational structure. However, since the method does not provide quantitative estimations of risk, it is recommended to be used as a complementary approach to the traditional risk assessments rather than as an alternative.

Novel Approach in Tunnel Safety Assessment

Accident Analysis and Prevention [Working Title]

The definition of a deterministic approach to risk analysis stems from the need to understand the conditions that are developed in the event of an accident with a fire in a road tunnel. From the point of view of the tunnel manager and rescuers, these data are important during planning the operation of the tunnel and in coordinating the rescue. The methods of tunnel control in crisis situations are most often based on the experience of operators and crisis plans, which are also made by experience or using simple calculation tools. In recent years, due to many tragic accidents in European tunnels, there has been a lot of talk and work in the field of risk assessment and the possibilities of risk reduction. The methodology of safety analyses and the determination of the level of risk arise predominantly from the nuclear and chemical industry, where it has been in use for more than 50 years. The paper presents the methodology for integrating methods of rapid processing of risk assessment with time-consuming CFD methods for analysing the consequences of fire in the tunnel safety assessment process. The main observed variables are the density and the temperature of the carbon black, which are analysed during the fire step in a minute. Human behaviour is considered in the evacuation model, which is necessary for the assessment of fatalities during the progress of the fire. The use of the methodology is presented by assessing the national tolerable risk for transport in tunnels and compared to the EU reference criteria.

Development of a Novel Quantitative Risk Assessment Tool for UK Road Tunnels

Fire

Some of the most critical transportation infrastructures are road tunnels. Underground passageways for motorists are provided through this cost-effective engineering solution, which allows for high traffic volumes. A crucial aspect of the operation of road tunnels is fire safety. Risk assessments have been established to ensure the level of safety in tunnels. As the existing quantitative risk analysis (QRA) models are inapplicable to assess the fire risk in UK road tunnels, this paper presents a novel QRA model, named LBAQRAMo, for UK road tunnels. This model consists of two main sections: quantitative frequency analysis, to estimate the frequency of fire incidents via an event tree; and quantitative consequences analysis, to model the consequences of fire incidents. LBAQRAMo covers the risk to tunnel users. The result of the risk analysis is the expected value of the societal risk of the investigated tunnel, presented via F/N curve. Another major result of this model is the estimat...

RISK ANALYSIS FOR SEVERE TRAFFIC ACCIDENTS IN ROAD TUNNELS (PART I)

The safety in road tunnels is a very delicate issue, since that a minor accident or a failure of a vehicle can degenerate into scenarios that can lead to a high number of victims. For example, on the 24 March 1999, 39 people died when a Belgian HGV carrying flour and margarine caught fire in the Mont Blanc Tunnel. In the first part of this study has been summarized the operation logic of a specific model for the risk analysis, the PIARC/OECD Quantitative Risk Assessment Model, and how it derives risk indicators. In the second part, a comprehensive risk analysis is performed in a long tunnel in South Italy, accounting for multifaceted aspects and parameters. The analysis is integrated with a sensitivity analysis on specific parameters that have an influence on the risk. In sections 2, 3, and 4 the concept of Risk and its assessment is dealt. In section 5, the proce-dure followed by the QRA model to derive societal and individual risk indicators is discussed, starting from a given number of possible accident scenarios. In section 6 conclusions are written regarding the application of the studied model.

RISK ANALYSIS FOR SEVERE TRAFFIC ACCIDENTS IN ROAD TUNNELS (PART II)

The safety in road tunnels is a very delicate issue, since that a minor accident or a failure of a vehicle can degenerate into scenarios that can lead to a high number of victims. For example, on the 24 March 1999, 39 people died when a Belgian HGV carrying flour and margarine caught fire in the Mont Blanc Tunnel. In the first part of this study has been summarized the operation logic of a specific model for the risk analysis, the PIARC/OECD Quantitative Risk Assessment Model, and how it derives risk indicators. In the second part, a comprehensive risk analysis is performed in a long tunnel in South Italy, accounting for multifaceted aspects and parameters. The analysis is integrated with a sensitivity analysis on specific parameters that have an influence on the risk. Section 2 of this paper describes the tunnel San Demetrio on which was carried out risk analysis applying the PIARC/OECD QRA model, and in the section 3 are reported the main analysis results. In section 4, conclusions regard to risk analysis applied to real case and about the sensitivity analysis are reported. In particular, the sensitivity analysis has highlighted the most influential parameters in the model.

RISK ANALYSIS FOR SEVERE TRAFFIC ACCIDENTS IN ROAD TUNNELS

Msc Thesis by Carmine Di Santo Advisor Franco Bontempi Co advisor Konstantions Gkoumas In this Thesis, a comprehensive risk analysis is performed in a long tunnel in South Italy, accounting for multifaceted aspects and parameters, using a dedicated tool (QRAM). The analysis is integrated with a sensitivity analysis on specific parameters that have an influence on the risk. In Chapter 2, the regulatory framework is discussed, which led to the identification of the quantitative risk analysis as the method for the determination of the inherent risk of a road tunnel. In Chapter 3, the procedure followed by the QRA model to derive societal and individual risk indicators is discussed, starting from a given number of possible accident scenarios. In chapters ranging from 4 to 7, physical phenomena of different accident scenarios are explained, and their consequences on the exposed population. In Chapter 8, is performed the risk analysis on the St. Demetrio tunnel applying the PIARC/OECD QRA model. In chapter 9, conclusions regard to risk analysis applied to real case and about the sensitivity analysis are appropriate. In particular, the sensitivity analysis has highlighted the most influential parameters in the model.

Mechanics FUZZY ANALYSIS OF TRAFFIC FLOWS FOR SAFETY TUNNEL SYSTEM

2007

Accidents that occurred in major road tunnels of European countries in the past pointed to the deficiency of safety management in these systems. Road tunnels represent a relatively weak link in road traffic communications in respect of safety. Tunnels are, as a matter of fact, relatively closed and not easily accessible places; their walls represent physical obstacles. In case of fire during transportation of flammable goods, freight or fuel, temperatures accumulated in the interior of the tunnel are high and resist for a relatively long time. Tunnel walls make heat dispersion difficult. In order to prevent undesirable events or at least reduce their incidence, specialists are trying to improve safety level in road tunnel systems by pursuing a safety policy by planning and making preparation for appropriate action in the event of such an occurrence. Fuzzy decisions allow effective control of safety and related hazards. They are based on the analysis of values that describe the condi...

Optimization of Road Tunnel Safety

Beton- und Stahlbetonbau, 2008

Probabilistic methods of risk optimization are applied to identify the most effective safety measures considered in design of road tunnels. The total consequences of alternative tunnel arrangements are assessed using Bayesian networks supplemented by decision and utility nodes. It is shown that the probabilistic optimization based on the comparison of societal and economic consequences may provide valuable information enabling a rational decision concerning effective safety measures. Thereby risk acceptability criteria are critically reviewed. A general procedure is illustrated by the optimization of a number of escape routes. It appears that the discount rate and specified life time of a tunnel affect the total consequences and the optimum arrangements of the tunnel more significantly than the number of escape routes. The optimum number of escape routes is also significantly dependent on the ratio of the cost of one escape route and acceptable expenses for averting a fatality based on the LQI. Further investigation of relevant input data including societal and economic consequences of various hazard scenarios as well as experience related to the effectiveness of safety systems are needed.