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Criteria and indicators are frequently used for assessing the resilience of Critical Infrastructures (CIs). However, the application of the concept of CIs resilience in practical disaster management is challenged by the lack of operational tools. An operational tool should enable the establishment of an organized system of indicators and optimising operational practice. Therefore, to address the operationalisation of resilience assessment, the main objective of this study is to develop a step-by-step guide for the creation of specific indicators aimed at different practical situations. This guide can assist CIs managers in their decision-making as it is structured based on a multi-criteria framework that considers the various interests of stakeholders. This guide includes the methods for Criteria and indicators setting, reference definition, and data collection. Furthermore, this study presents an example of the application of the guide. This example is based on a given scenario focusing on the Nantes Ring Road (NRR) network: when it is flooded and closed, the road network manager suggests alternative roads to citizens. The created indicators, based on this scenario and involved 62 676 data, relate to potential damages and costs-benefit and involve technical, social, and environmental dimensions. [ABSTRACT FROM AUTHOR]

The present work develops an integrated rapid loss assessment model aiming to quickly estimate the expected damages and their spatial distribution for the Algerian urban heritage context. It predicts the expected damages for a given earthquake scenario, i.e. an historic event or a reference scenario. Furthermore, in the immediate aftermath of an earthquake, the model updates the damages according to the seismic signals either recorded in the zone of interest or derived quickly from the GMPE (Ground Motion Prediction Equations). It combines a seismic damage assessment approach developed for existing building in Algeria and a GIS system, in order to automatically generate relevant damage maps for decision-making and rescue purposes. It is implemented and run for a real case of Blida city, located in the central northern part of Algeria, which is a highly dense urban area (3070 inhabitants/km2) containing an important architectural and historical heritage. For calibration purposes, the model is implemented and run in order to generate the seismic damage GIS maps for a set of 23,000 buildings, for a potential earthquake Mw = 7, consistent with the area seismicity. The results show that serious damages and complete destruction are expected in particular areas, mainly the oldest districts with an urban heritage consisting of old unreinforced masonry buildings dating from the XVI to the middle of the XX centuries. Less important damages are expected for newly erected constructions built during and after the last half of the XX century, as they meet the structural design standards and built on adequate soils. [ABSTRACT FROM AUTHOR]

Concerns about the risk of catastrophic accidents have prompted governments and industries to develop new methods for identifying and evaluating potential hazards. The most promising strategy involves assembling a collection of quantitative risk assessment techniques (QRA). The use of (QRA) is rapidly spreading across industries, having been adapted primarily from probabilistic risk assessment approaches developed in other industries. The Netherlands Organization (TNO) developed the (QRA) for the external safety of industrial plants against fire and explosion hazards. Escalation of primary events that trigger accidental scenarios may have a significant impact on industrial risk, increasing the overall expected frequency of single scenarios and resulting in extremely severe damages involving multiple plant units simultaneously. The present study applied a methodology developed for quantifying the risk of liquefied natural gas (LNG) containment loss. To begin, an industrial facility is separated into modules based on its structural characteristics. Following that, the relevant fire and explosion scenarios are identified, along with their frequency of occurrence. Recently developed equipment damage probability models were used to determine the probability of the final scenario occurring. SAFETI software was used to model and calculate risks. Finally, the individual risks (thermal and overpressure exceedance curves) are calculated, as well as the societal risk (FN curve). The findings demonstrate the critical importance of quantitative risk assessment in identifying critical equipment and addressing prevention and protection measures. [ABSTRACT FROM AUTHOR]

Obstacles are unavoidable in coalmine laneways and combustible gas pipeline. However, the obstacles may enhance the intensity of explosion, or change the propagation characteristic. The present paper deals with the flame propagation characteristic of explosion in the tube with a tilted obstacle (45 ~ 135°) under the condition of low initial pressure (0.2 ~ 0.35 kPa). Two models (a so-called modified model and a mathematical model) are adopted in order to describe the regularity of flame velocity for the first (i.e. after explosion at an edge of the tube) and third (i.e. before the flame reaches the end of the tube) stages, whereas some irregular phenomena are investigated during the second stage (i.e. in which the flame reaches the titled obstacle, and goes beyond it) of the whole process, i.e. explosion and flame propagation along the tube. A theoretical fitting model is built in order to describe the critical moments of the accident, i.e. explosion and propagation. It is shown that the initial pressure and obstacle, considered as governing factors, have specific influences on flameless zone and flame velocity. This research can provide a new basic study of the effects of obstacles on combustible gas explosion and a reference for actual explosion protection designs. [ABSTRACT FROM AUTHOR]

This study uses interferometric SAR techniques to identify landslides and lands prone to landslides, detect fringes and changes in areas struck by earthquakes. The pilot study investigates the Mila region (Algeria) which suffered significant landslides and structural damages (earthquake: Mw 5, 2020-08-07): the study checks ground deformations and tracks earthquake-induced landslides. DInSAR analysis shows normal interferograms, with atmospheric contribution, and slight fringes. However, it identifies many landslides, the most important (2.5 m displacement) being located in Kherba neighborhood, causing severe damages to dwellings. In addition, SAR images and optical images (Sentinel-2) confirm site investigations. Although in Grarem City, optical images could not detect any disorder, the DInSAR analysis detected some coherence decays and small fringes (3.94 km2 area). These unnoticed ground disorders were confirmed during fields inspection. Such results have key importance since they can serve as an alert to monitor the zone at the proper time. Furthermore, Displacement time series analysis of many interferograms (April 2015 to September 2020) using LiCSBAS were performed to investigate the pre-event conditions and precursors of the slopes instabilities., LiCSBAS detects a line-of-sight subsidence velocity of -110 mm/y in the back hillside of Kherba, and high displacement velocity at specific points in Grarem region. [ABSTRACT FROM AUTHOR]