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We present a framework for the seismic risk assessment of water supply networks, operating in either normal or abnormal conditions. We propose a methodology for assessing the reliability of water pipe networks combining data of past non-seismic damage and the vulnerability of the network components against seismic loading. Historical data are obtained using records of damages that occur on a daily basis throughout the network and are processed to produce'survival curves', depicting their estimated survival rate over time. The fragility of the network components is assessed using the approach suggested in the American Lifelines Alliance guidelines. The network reliability is assessed using graph theory, whereas the system network reliability is calculated using Monte Carlo simulation. The methodology proposed is demonstrated both on a simple, small-scale, network and also on a real-scale district metered area from the water network of the city of Limassol, Cyprus. The proposed approach allows the estimation of the probability that the network fails to provide the desired level of service and allows the prioritization of retrofit interventions and of capacity-upgrade actions pertaining to existing water pipe networks. Copyright copyright 2013 John Wiley & Sons, Ltd. 43 3 357 374

The concept of disaster resilience has received considerable attention in recent years and it is increasingly used as an approach for understanding the dynamics of natural disaster systems. No models are available in literature to measure the performance of natural gas network, therefore, in this paper, a new performance index measuring functionality of gas distribution network have been proposed to evaluate the resilience index of the entire network. It can be used for any type of natural or manmade hazard which might lead to the disruption of the system. The gas distribution network of the municipalities of Introdacqua and Sulmona, two small towns in the center of Italy which were affected by 2009 earthquake have been used as case study. Together the pipeline network covers an area of 136 km2, with 3 M/R stations and 16 regulation groups. The software SynerGEE has been used to simulate different scenario events. The numerical results showed that, during emergency, to ensure an acceptable delivery service, it is crucial to guarantee the functionality of the medium pressure gas distribution network. Instead to improve resilience of the entire network the best retrofit strategy is to include emergency shutoff valves along the pipes.

This January 17 earthquake was a killer earthquake that struck one of the world's largest port cities. As of June 30, the toll from the earthquake in the Kansai region was 5,502 dead, 2 missing, and 39,708 injured. More than half or the dead were over 60 years old. Inner city problems such as densely populated urban areas with old wooden houses and very narrow streets intensified the severity of damage. More than 500,000 houses and buildings were partially or completely destroyed. The slow start of the search and rescue operations and lack of emergency management increased the human and property damage. The redundancy of the water supply systems and quick recovery of electric power contributed to the stabilization or the regional society in spite of the massive damage. The maximum number of evacuees at shelters was 316,678 on January 23; about 20,000 remained on June 30, About 60,000 temporary housing units were planned and some were completed as early as the second week after the earthquake. During these first two weeks, the number of residents rescued in Kobe City was l,888 but those surviving only 733. The total number of fires in Kobe was 176, and the area burned about 70 ha. In terms of economic damage, the loss of property was 11.6 trillion Japanese yen, 2.5% of the Japanese GDP (466 trillion Japanese yen in 1994).

One of the most critical lessons of the recent earthquakes is the need for seismic planning for lifelines, with appropriate supplies and back up systems for emergency repair and restoration. Seismic planning, however requires physical loss estimations before the earthquakes occur. Buried pipeline damage correlations are critical part of loss estimation procedures applied to lifelines for future earthquakes. We review the existing pipeline damage relationships only for ground shaking (transient ground deformations) in the light of recent developments and evaluate them with Denizli City, Turkey water supply system. Eight scenario earthquakes with four different earthquake magnitudes between M6 and M7 caused by two different fault ruptures (Pamukkale and Karakova-Akhan Faults) were used. Analyses were performed by using Geographical Information Systems (GIS). This high number of different scenario earthquakes made it possible to compare the pipeline damage relationships at different ground shaking levels. Pipeline damage estimations for Denizli City were calculated for each damage relationship and earthquake scenario. Relative effects of damage relationships and scenario earthquakes on the results were compared and discussed. The results were presented separately for brittle, ductile, and all pipelines. It was shown that the variation in ductile pipeline damage estimations by various relationships was higher than the variation in brittle pipeline damage estimations for a particular scenario earthquake. © Springer 2006.

One of the most critical lessons of the recent earthquakes is the need for seismic planning for lifelines, with appropriate supplies and back up systems for emergency repair and restoration. Seismic planning, however requires physical loss estimations before the earthquakes occur. Buried pipeline damage correlations are critical part of loss estimation procedures applied to lifelines for future earthquakes. We review the existing pipeline damage relationships only for ground shaking (transient ground deformations) in the light of recent developments and evaluate them with Denizli City, Turkey water supply system. Eight scenario earthquakes with four different earthquake magnitudes between M6 and M7 caused by two different fault ruptures (Pamukkale and Karakova-Akhan Faults) were used. Analyses were performed by using Geographical Information Systems (GIS). This high number of different scenario earthquakes made it possible to compare the pipeline damage relationships at different ground shaking levels. Pipeline damage estimations for Denizli City were calculated for each damage relationship and earthquake scenario. Relative effects of damage relationships and scenario earthquakes on the results were compared and discussed. The results were presented separately for brittle, ductile, and all pipelines. It was shown that the variation in ductile pipeline damage estimations by various relationships was higher than the variation in brittle pipeline damage estimations for a particular scenario earthquake.

In past works the authors set up a refined model for electric power networks under earthquake action. The procedure models the fragility of components with respect to earthquake action, the complex behaviour of the stations and the network, the power flow, the network capability to feed the nodes in a damaged condition, the earthquake damage on the territory, the need to deliver electric power to the municipalities where most damage has occurred. In later works the method was improved towards design goals: nonetheless complexity of the network seismic behaviour, a procedure to maximize safety of selected nodes and minimize economic expenses was constructed, allowing identification of which components, within each station, had to be upgraded to obtain the maximum economic convenience. The procedure was programmed within the ASK4ELP computer code (National Information Service for Earthquake Engineering, University of California, Berkeley, U.S.A., 1999) using late 1990s state-of-the-art knowledge for both the earthquake and the structural behaviour models. Recently the method has gone through a thorough updating, partially still in progress. Among the results, it is now more clear how important is a correct soil geotechnical model to predict the system response and safety. This paper presents, together with a short summary of the ASK4ELP procedure, these latest advancements and results and shows, through a real example, the sensitivity of the predicted safety to soil modelling.

The optimization of preventive upgrading interventions on the bridges of a highway network in an earthquake prone area is tackled. The bridges are assumed to be the vulnerable elements of the network, whose main purpose is to connect two sites. If the probability of collapse of each bridge under an earthquake of given intensity is known, the topology of the network allows us to calculate its reliability, i.e., the probability of maintaining the connection between the source node and the destination node. To increase the reliability, preventive upgrading interventions must be designed: the main purpose of this study is to present a procedure, based on dynamic programming, which is able to distribute the interventions among the bridges so that, for a given total amount of employed resources, the increase in reliability is maximized. The applicability of the procedure is demonstrated by some complete numerical examples. Alternative choices of the objective function and other further developments are also discussed.

A review of the current state-of-knowledge in risk-based earthquake-resistant design of pipeline systems is presented. Damage to pipelines during past earthquakes is studied, and the necessity of evaluating the risk to such systems from earthquakes for their economic design is illustrated. The various aspects of seismic risk analysis of pipeline systems are briefly studied and a conclusion reached that given a tectonic and seismic data for the region in which pipelines lie, in addition to proper definition of various levels of pipeline unserviceability, it is possible to estimate the earthquake hazards to such pipelines with a reasonable degree of accuracy. Since this subject is of topical interest to this country, with increasing number of pipeline systems laid in earthquake-prone areas, specific areas are identified where more information is required before meaningful seismic risk analysis of pipelines can be done in India.

Nowadays, underground structures play vital role in developing different countries. Such structures are constructed in many civil activities such as development of road and railways, subways, water, gas and sewage lines, underground subways, nuclear wastes land filling, fuel storage and military installations. With an appropriate drilling method being selected, instabilities created in tunnels may be controlled, the volume of maintenance systems required in structures may be decreased, and extra costs arising from it may be decreased as well. Excavation of surface tunnels may bring about changes on the surface and in the adjacent structures. Settlement on the surface and instabilities in adjacent structures as a result of stress induction are among the most important changes of this kind. Plaxis software has been used in the research to evaluate the technical parameters of tunnel such as tunnel diameter, tunnel depth from the earth surface, drilling method and distance from adjacent structures. Meanwhile it investigates the effects of urban tunnel drilling as lifelines on adjacent structures and render the results in the form of a diagram.

The present paper proposes a new methodology to characterize the landslide susceptibility of Reggio Calabria territory. The values obtained were classified into five categories: very low, low, medium, high and very high, and were than exported into GIS environment to produce a landslide susceptibility map. The principal objective of the proposed study is to identify the sections of the road network exposed to landslide hazards starting from the susceptibility map. To this aim, a fuzzy system was designed with 2 input, 15 rules “if-then” and 1 output representing the “level of attention” for the considered transport infrastructure, being a higher value of attention level correspondent to a higher landslide hazard. From the obtained results it is possible to notice that the most relevant roads in terms of connection, as the highway A3, the road SS106 and other roads linking the Ionian Coast to the Tirrenic Coast, are those displaying the highest level of attention.