Serge Lhomme

A methodology to produce interdependent networks disturbance scenarios .

Quick urban development coupled with technical failures and climate change have increased flood risk and corresponding challenges to urban flood risk management. In this context, there is a need to understand how networked systems are resilient because societal functions are highly dependent on networked systems and the operability of these systems can be vulnerable to disasters. That is why we develop a methodology for producing interdependent networks disturbance scenarios. In order to take advantage of this methodology software is needed.

Assessing Vulnerability to Floods of the Built Environment-Integrating Urban Networks and Buildings

The EU is very concerned by flood risk. The effects of floods on urban areas are substantial in terms of damage and economic loss. It is expected, taking into account climate change and urban growth, that this particular risk will be more frequent and will cause more and more damage; the built environment has become very vulnerable to floods. There is a need to develop methods and tools to assess urban vulnerability to floods. Indeed, some solutions are already available to assess vulnerability of buildings or infrastructure such as networks. But, the city is a complex system and not just a sum of its components. Our purpose is about developing techniques to assess the vulnerability of the city using a systematic approach and integrating existing tools which assess the vulnerability of particular components of the city system.

L’importance de la redondance comme facteur de résilience des réseaux techniques. Contribution à l’élaboration d’un indicateur spatial de redondance

La resilience est un concept de plus en plus utilise en gestion des risques. Elle peut etre definie comme la plus ou moins grande capacite d’un systeme a absorber une perturbation et a recuperer ses fonctions a la suite de cette perturbation. La recherche d’indicateurs de resilience est des lors necessaire pour rendre ce concept operationnel. Concernant les reseaux techniques, la redondance constitue une caracteristique importante en matiere de resilience. C’est pourquoi, des indicateurs de redondance ont ete developpes puis testes sur des reseaux reels afin d’evaluer leur pertinence a l’aide d’un SIG. Ces indicateurs peuvent etre agreges afin de definir un indicateur spatial de redondance.

Integrating flood defence fragility to measure built environment vulnerability - a GIS based approach

More and more floods occurred over the last decade in the world, causing important damages. Moreover, levees are often not well maintained, so they hardly resist to major floods and can break easily. At French national scale, the length of levees, estimated to 7500 kilometers, and the lack of data all along these infrastructures complicates their management. In this frame, levee managers need approaches and tools in order to be helped in their maintenance decision. The goal of our research is to develop methods modeling levee failure mechanisms and allowing performance levee assessment. These methods integrated in an existing GIS dedicated to levee management will contribute to obtain a spatial decision support system aiding levee managers in their maintenance decision. Finally we made some tests in a specific area to integrate in the SDSS the level of vulnerability behind dikes to improve the levee manager decision process.