The application of a Bayesian approach to assess the seismic vulnerability of historical centers

The seismic vulnerability of historical centers at a territorial scale cannot be assessed performing detailed analysis which are usually adopted at the single building scale. In fact, a traditional complete survey would be extremely time-consuming and not sustainable for this purpose. The approach described in this paper is based on the idea that it is possible to infer quantities which cannot be directly detected from buildings outside inspection starting from parameters that can be measured. In order to achieve this purpose, a Bayesian approach is applied, updating initial hypotheses when new data become available. In this context, the procedure herein proposed aims at applying a probabilistic approach instead of a deterministic one to define facades inter-storey height starting from buildings height knowledge. In order to validate the method, for out of plane local mechanisms of collapse (walls overturning), horizontal loads multiplier \uf0610 values are calculated and compared to results obtained by using data collected on-site

RANGELAND FIRES IN NORTHERN NEVADA: AN APPLICATION OF COMPUTABLE GENERAL EQUILIBRIUM MODELING

Resource /Energy Economics and Policy,

Seismic Retrofit for Electric Power Systems

This paper develops a two-stage stochastic program and solution procedure to optimize the selection of seismic retrofit strategies to increase the resilience of electric power systems to earthquake hazards. The model explicitly considers the range of earthquake events that are possible and, for each, an approximation to the distribution of damage that is experienced. This is important because electric power systems are spatially distributed; hence their performance is driven by the distribution of damage of the components. We test this solution procedure against the nonlinear integer solver in LINGO 13 and apply the formulation and solution strategy to the Eastern Interconnection where the seismic hazard stems from the New Madrid Seismic Zone

Performance Measures to Assess Resiliency and Efficiency of Transit Systems

Transit agencies are interested in assessing the short-, mid-, and long-term performance of infrastructure with the objective of enhancing resiliency and efficiency. This report addresses three distinct aspects of New Jersey’s Transit System: 1) resiliency of bridge infrastructure, 2) resiliency of public transit systems, and 3) efficiency of transit systems with an emphasis on paratransit service. This project proposed a conceptual framework to assess the performance and resiliency for bridge structures in a transit network before and after disasters utilizing structural health monitoring (SHM), finite element (FE) modeling and remote sensing using Interferometric Synthetic Aperture Radar (InSAR). The public transit systems in NY/NJ were analyzed based on their vulnerability, resiliency, and efficiency in recovery following a major natural disaster

Seismic Risk Analysis of Revenue Losses, Gross Regional Product and transportation systems.

Natural threats like earthquakes, hurricanes or tsunamis have shown seri- ous impacts on communities. In the past, major earthquakes in the United States like Loma Prieta 1989, Northridge 1994, or recent events in Italy like L’Aquila 2009 or Emilia 2012 earthquake emphasized the importance of pre- paredness and awareness to reduce social impacts. Earthquakes impacted businesses and dramatically reduced the gross regional product. Seismic Hazard is traditionally assessed using Probabilistic Seismic Hazard Anal- ysis (PSHA). PSHA well represents the hazard at a specific location, but it’s unsatisfactory for spatially distributed systems. Scenario earthquakes overcome the problem representing the actual distribution of shaking over a spatially distributed system. The performance of distributed productive systems during the recovery process needs to be explored. Scenario earthquakes have been used to assess the risk in bridge networks and the social losses in terms of gross regional product reduction. The proposed method for scenario earthquakes has been applied to a real case study: Treviso, a city in the North East of Italy. The proposed method for scenario earthquakes requires three models: one representation of the sources (Italian Seismogenic Zonation 9), one attenuation relationship (Sa- betta and Pugliese 1996) and a model of the occurrence rate of magnitudes (Gutenberg Richter). A methodology has been proposed to reduce thou- sands of scenarios to a subset consistent with the hazard at each location. Earthquake scenarios, along with Mote Carlo method, have been used to simulate business damage. The response of business facilities to earthquake has been obtained from fragility curves for precast industrial building. Fur- thermore, from business damage the reduction of productivity has been simulated using economic data from the National statistical service and a proposed piecewise “loss of functionality model”. To simulate the economic process in the time domain, an innovative businesses recovery function has been proposed. The proposed method has been applied to generate scenarios earthquakes at the location of bridges and business areas. The proposed selection method- ology has been applied to reduce 8000 scenarios to a subset of 60. Subse- quently, these scenario earthquakes have been used to calculate three system performance parameters: the risk in transportation networks, the risk in terms of business damage and the losses of gross regional product. A novel model for business recovery process has been tested. The proposed model has been used to represent the business recovery process and simulate the effects of government aids allocated for reconstruction. The proposed method has efficiently modeled the seismic hazard using scenario earthquakes. The scenario earthquakes presented have been used to assess possible consequences of earthquakes in seismic prone zones and to increase the preparedness. Scenario earthquakes have been used to sim- ulate the effects to economy of the impacted area; a significant Gross Regional Product reduction has been shown, up to 77% with an earthquake with 0.0003 probability of occurrence. The results showed that limited funds available after the disaster can be distributed in a more efficient way

Computer-aided decision making for regional seismic risk mitigation accounting for limited economic resources

Seismic risk mitigation levels for an existing building are a balance between the reduction of risk and the cost of rehabilitation. Evidently, the more that is paid the more risk is reduced; however, due to limited public budgets a practical approach is needed to manage the risk reduction program when a portfolio of buildings is concerned. Basically, decision makers face a challenge when there are a large number of vulnerable buildings and there is no plan for how to allocate the appointed budget. This study develops a technological platform that implements a decision-making procedure to establish how to optimally distribute the budget in order to achieve the maximum possible portfolio risk reduction. Decisions are made based on various presumed intervention strategies dependent on building’s level of risk. The technological platform provides an interactive, user-friendly tool, available online, that supports stakeholders and decision makers in understanding what the best economic resource allocation will be after selecting the available budget for a specific portfolio of buildings. In addition, the ease of use enables the user to analyze the extent of risk reduction achievable for different budget levels. Therefore, the web platform represents a powerful tool to accomplish two challenging tasks, namely optimal budget selection and optimal budget allocation to gain territorial seismic risk mitigation

Seismic and energy retrofitting of residential buildings: a simulation-based approach

The topic of the high seismic vulnerability of housing stock in Italy is back again at the center of political, economic, social and scientific-technical debate following the seismic crisis that struck Marche, Umbria and Lazio regions in 2016. These events have once again raised the need for a massive retrofitting program at National and Regional level, addressing the majority of the existing building stock, realized for 60% prior to the adoption of the first seismic code (Law 64/74), in a territory characterized north to south by high levels of seismic hazard. In recent years, different kinds of tools have been implemented to allow the simulation of natural hazards’ impacts on the built environment and to support strategic choices both in the field of emergency management and resilience-based urban design and planning. Nevertheless, an integrated set of instruments for a quantitatively informed decision support is still missing. Within EU-FP7 CRISMA project, an integrated DSS (Decision Support System) application has been developed, with a set of tools and functionalities addressing the main aspects involved in the decision-making processes for natural hazards preparedness and response