La vulnérabilité des infrastructures ferroviaires face aux évènements hydrologiques extrêmes. État des connaissances et gestion du risque

Le chemin de fer s'est développé en France dès le début du 19ème siècle pour le transport de marchandises dans un premier temps et le transport de voyageurs par la suite. Le 20ème siècle a vu son essor avec la desserte de tout le territoire, y compris des zones de montagne et plus tard l'arrivée des lignes à grande vitesse. En plus de croiser de nombreux cours d'eau, les voies ferrées contraintes par leur profil en long impactent fortement le relief et modifie parfois les écoulements naturels avec des conséquences pour la sécurité des circulations ferroviaires et des riverains. La Garonne en 1875, la Seine en 1910, l'Aude en 1999 ou le Rhône en 2003 ont marqué l'histoire du chemin de fer. Les sociétés de chemin de fer ont été confrontées à des aléas hydrologiques extrêmes, tant lors des travaux qu'en cours d'exploitation des lignes. L'ingénierie ferroviaire s'est enrichie de cette connaissance empirique pour la reconstruction des ouvrages détruits mais également lors de la conception des projets nouveaux. La prise en compte de ces aléas extrêmes lors de la conception a également évolué en empruntant des méthodes aux autoroutiers, en appliquant la loi sur l'eau et en intégrant le principe de transparence hydraulique. Cette évolution continue de nos jours pour améliorer la cohabitation des ouvrages ferroviaires et des cours d'eau, et mieux gérer le risque hydraulique

La vulnérabilité des infrastructures ferroviaires face aux évènements hydrologiques extrêmes. Etat des connaissances et gestion du risque.

Railway vulnerability in case of extremes floods. Knowledge and risk management. The railway transportation has been developed since 19th century first for loading and then for people. During the 20th century, railway spreads in all France even in mountains area, and later the high speed railway grows. The tracks cross rivers and because of their longitudinal section, they modify drastically the relief and consequently the natural flows with impacts for railway security and adjoining population. The Garonne river in 1875, the Seine river in 1910, the Aude river in 1999 or the Rhône river in 2003 remain in memory of rail transport. Railway companies were faced to extreme flood events during works and service. Railway engineering used this empirical knowledge not only to rebuild destroyed structures but also to improve the design of the new project. To better take in account extremes floods in design, rail engineering also lent highway knowledge developed in 1960s, followed french water law since 1992 and integrated hydraulic transparency principle. The evolution continues nowadays to improve the cohabitation of rail works with rivers and to better manage hydraulic risk.Le chemin de fer s’est développé en France dès le début du 19ème siècle pour le transport de marchandises dans un premier temps et le transport de voyageurs par la suite. Le 20ème siècle a vu son essor avec la desserte de tout le territoire, y compris des zones de montagne et plus tard l’arrivée des lignes à grande vitesse. En plus de croiser de nouveaux cours d’eau, les voies ferrées contraintes par leur profil en long impactent fortement le relief et modifie parfois les écoulements naturels avec des conséquences pour la sécurité des circulations ferroviaires et des riverains. La Garonne en 1875, la Seine en 1910, l’Aude en 1999 ou le Rhône en 2003 ont marqué l’histoire du chemin de fer. Les sociétés de chemin de fer ont été confrontées à des aléas hydrologiques extrêmes, tant lors des travaux qu’en cours d’exploitation des lignes. L’ingénierie ferroviaire s’est enrichie de cette connaissance empirique pour la reconstruction des ouvrages détruits mais également lors de la conception des projets nouveaux. La prise en compte de ces aléas extrêmes lors de la conception a également évolué en empruntant des méthodes aux autoroutiers, en appliquant la loi sur l’eau et en intégrant le principe de transparence hydraulique. Cette évolution continue de nos jours pour améliorer la cohabitation des ouvrages ferroviaires et des cours d’ea, et mieux gérer le risque hydraulique.Chazelle Blandine, Lambert Lucie, Pams-Capoccioni Cicely. La vulnérabilité des infrastructures ferroviaires face aux évènements hydrologiques extrêmes. Etat des connaissances et gestion du risque.. In: Evénements extrêmes fluviaux et maritimes. Leurs variabilités spatiales et chronologiques dans l'ouest de l’Europe. 34èmes journées de l’hydraulique Paris, 1 et 2 février 2012. 2012

Use of post-event surveys of impacts on railways for the evaluation of the IRIP method for surface runoff mapping

IRIP – Indicator of Intense Pluvial Runoff (French Acronym) – is a method to map the susceptibility of territories to surface runoff generation, transfer and accumulation. The method is based on a geomatic combination of landscape factors extracted from topography, land use and soil type. This study is part of the method evaluation process and suggests using information from post-event surveys of surface runoff events to evaluate the agreement between the IRIP maps and the field observations. Surface runoff susceptibility maps are produced at five meters resolution for three impact areas on railways with different infrastructure and environment configurations. First, information categories are extracted from the post-event surveys, and then the IRIP maps are analyzed to see if and how the information categories are retrieved. This study shows that the IRIP maps fit the impact description. The areas susceptible to surface runoff transfer fit the gullies locations and the areas susceptible to surface runoff accumulation fit the sediment deposit traces. The comparison also highlights that the IRIP maps can give further information on the event spatial dynamics. Given the simplicity and the robustness of the mapping method, IRIP can be a tool to perform surface runoff post-event surveys and to improve the surface runoff hazard assessment

Innovation to maintain complex systems for transitions: organizing for innovative validation

International audienc

Renovating engineering departements' creation heritage to meet contemporary challenges: frugal validation patterns and constructive proof logics for new engineering rules

International audienceEngineering departments design infrastructure by applying rule systems. The latter are an old creation heritage, based on decades of engineering, that makes it possible to design and govern the operation of the physical heritage which is the infrastructure. Replacing the infrastructure is not sustainable in the meaning of grand challenges; renovating it by applying engineering rules is but could appear too expensive. The literature highlights situations where renovation by respecting the state of the art is too costly and so is the validation of new renovation rules. Are there forms of frugal validation that allow for sustainable renovation of existing systems? This paper tries to explore a third way, a renovation of the physical heritage from a renovation of the system of rules, conceiving in the system of rules, new propositions, and their validation. Using the C-K theory, a case analysis was performed within the French national rail network manager (SNCF Network), a company that has a historical engineering heritage and is at the same time implementing a renovation of it. The paper shows that the renovation of engineering departments' creation heritage can go through frugal validation patterns and constructive proof logics

Utilisation de rapports post-incident d'impacts sur voie ferrée pour l'évaluation de la méthode IRIP de cartographie du ruissellement

FloodRisk, 3rd European Conference on Flood Risk Management, Lyon, FRA, 17-/10/2016 - 21/10/2016; International audience; Indicator of Intense Pluvial Runoff (French Acronym) - is a method to map the susceptibility of territories to surface runoff generation, transfer and accumulation. The method is based on a geomatic combination of landscape factors extracted from topography, land use and soil type. This study is part of the method evaluation process and suggests using information from post-event surveys of surface runoff events to evaluate the agreement between the IRIP maps and the field observations. Surface runoff susceptibility maps are produced at five meters resolution for three impact areas on railways with different infrastructure and environment configurations. First, information categories are extracted from the post-event surveys, and then the IRIP maps are analyzed to see if and how the information categories are retrieved. This study shows that the IRIP maps fit the impact description. The areas susceptible to surface runoff transfer fit the gullies locations and the areas susceptible to surface runoff accumulation fit the sediment deposit traces. The comparison also highlights that the IRIP maps can give further information on the event spatial dynamics. Given the simplicity and the robustness of the mapping method, IRIP can be a tool to perform surface runoff post-event surveys and to improve the surface runoff hazard assessment

A method to use proxy data of runoff-related impacts for the evaluation of a model mapping intense storm runoff hazard: application to the railway context

International audienceThe TRIP method, or "indicator of intense pluvial runoff" in English, is a geomatics method that allows mapping the susceptibility of a territory to surface runoff and that provides three maps of susceptibility to the generation, transfer and accumulation of runoff. It is based on the combination of binary maps that represent the impact of a given factor (favourable or not favourable) on runoff. These factors are summed up to provide susceptibility maps for runoff with levels ranging from 0 to 5. To be used for risk prevention, the quality and limitations of the produced maps must be assessed. However, direct runoff data are very scarce and not available everywhere in a territory. Proxy data of impacts related to runoff can provide information useful for the evaluation of the IRIP maps. However, both pieces of information cannot be compared directly, and a specific methodology to compare susceptibility maps and proxy data must be proposed. This paper presents such a method, which accounts for the hazard level, the vulnerability of the study area and possible mitigation actions taken to reduce the risk. The evaluation method is assessed using a comprehensive database of runoff-related impacts collected on an 80 km railway line in Normandy (north of France) and covering the whole 20th century. The results show that the evaluation method is robust, relevant and generic enough for evaluating a non-quantitative method of runoff hazard mapping using localized runoff-related proxy data. In addition, the good performance of the IRIP model in the case study confirms that the susceptibility maps produced by the IRIP model provide relevant information related to runoff and that they can be used to design risk management strategies, as illustrated in the railway context

Use of post-event surveys of impacts on railways for the evaluation of the IRIP method for surface runoff mapping

IRIP – Indicator of Intense Pluvial Runoff (French Acronym) – is a method to map the susceptibility of territories to surface runoff generation, transfer and accumulation. The method is based on a geomatic combination of landscape factors extracted from topography, land use and soil type. This study is part of the method evaluation process and suggests using information from post-event surveys of surface runoff events to evaluate the agreement between the IRIP maps and the field observations. Surface runoff susceptibility maps are produced at five meters resolution for three impact areas on railways with different infrastructure and environment configurations. First, information categories are extracted from the post-event surveys, and then the IRIP maps are analyzed to see if and how the information categories are retrieved. This study shows that the IRIP maps fit the impact description. The areas susceptible to surface runoff transfer fit the gullies locations and the areas susceptible to surface runoff accumulation fit the sediment deposit traces. The comparison also highlights that the IRIP maps can give further information on the event spatial dynamics. Given the simplicity and the robustness of the mapping method, IRIP can be a tool to perform surface runoff post-event surveys and to improve the surface runoff hazard assessment

Renovating engineering departements' creation heritage to meet contemporary challenges: frugal validation patterns and constructive proof logics for new engineering rules

International audienceEngineering departments design infrastructure by applying rule systems. The latter are an old creation heritage, based on decades of engineering, that makes it possible to design and govern the operation of the physical heritage which is the infrastructure. Replacing the infrastructure is not sustainable in the meaning of grand challenges; renovating it by applying engineering rules is but could appear too expensive. The literature highlights situations where renovation by respecting the state of the art is too costly and so is the validation of new renovation rules. Are there forms of frugal validation that allow for sustainable renovation of existing systems? This paper tries to explore a third way, a renovation of the physical heritage from a renovation of the system of rules, conceiving in the system of rules, new propositions, and their validation. Using the C-K theory, a case analysis was performed within the French national rail network manager (SNCF Network), a company that has a historical engineering heritage and is at the same time implementing a renovation of it. The paper shows that the renovation of engineering departments' creation heritage can go through frugal validation patterns and constructive proof logics

Innovation to renovate complex systems for transitions: organizing for innovative validation

International audienc