Seismic Risk Assessment Methodology Research Articles

The Seismic Evaluation of Existing Buildings for Energy Renovation—A Case Study for the Residential Building Stock in Bucharest (Romania)

This study focuses on an overview of two programs applied to the residential building stock of Bucharest (Romania), namely, the seismic strengthening program and the thermal rehabilitation program. The methodology for seismic risk assessment given in the current generation of Romanian codes, as well as in previous regulations, is examined. A brief review of other seismic risk assessment methodologies currently applied in various seismically prone countries is also presented. Examples of high-rise buildings in Bucharest that suffered significant damage during the Vrancea 1977 earthquake and that were thermally rehabilitated without any strengthening works are shown in this paper. The consistent differences between the current outcomes of the two programs are presented and discussed. Finally, this review paper highlights the lack of coherence in terms of seismic risk assessments for the same class of buildings, inducing, in some situations, a false feeling of safety in the building inhabitants. In addition, a combined procedure for both seismic strengthening and thermal rehabilitation is mandatory, considering the seismicity of Romania, as well as ongoing climate change.

Planning for More Resilient and Safer Cities: A New Methodology for Seismic Risk Assessment at the Urban Scale, Applied to a Case Study in Italy

Recent seismic events and the damages related to them have highlighted the crucial role of urban planning in coping with the fragility and intrinsic vulnerability of cities. The paper presents a methodology for assessing seismic risk at an urban scale, expanding from a single-building investigation to an urban-scale analysis by adopting an empirical method for assessing the vulnerability of the urban fabric. Data collection and analysis have been conducted through the Geographic Information System (GIS). The methodology has been applied to the Italian city of Castelfranco Emilia, in the Emilia-Romagna region, where the current regional urban planning law is guiding municipalities towards the development of strategies mostly oriented toward the retrofit of the existing building stock and the overall regeneration of the urbanized territory, in accordance with the target of no net land take by 2050. The novelty of the method stands in the transposition of approaches born in the civil engineering and protection domains to the urban planning sphere, stressing the importance of developing urban planning instruments which are well-integrated with vulnerability assessments and, therefore, able to successfully incorporate risk considerations in the decision making.

Simplified pushover-based seismic risk assessment methodology for existing infilled frame structures

Simplified pushover-based seismic risk assessment methodology for existing infilled frame structures

Seismic risk assessment in transboundary areas: the case study on the border between Italy and Slovenia

An important aspect to take into account in the process of prevention, mitigation, preparedness and response to catastrophes is the risk assessment in transboundary areas that is not yet harmonized. Indeed, transboundary risk assessment cannot be based directly on national risk assessment because the neighbouring countries use different risk assessment methodologies and levels of detail. To address this issue, a harmonisation process should be implemented to establish the use of shared approaches and employ common data types and analysis models, which allow representing the impact of the seismic hazards in a shared framework among the countries. This paper illustrates the proposed methodology for seismic risk assessment in the area on the border between Italy and Slovenia, in particular in the region near Gorizia and Nova Gorica. This activity is one of the products of the BORIS project (Cross BOrder RISk assessment for increased prevention and preparedness in Europe) that focuses on the assessment of seismic risk and flood risk, having cross-border impact potential in several countries participating in the Union Civil Protection Mechanism. Furthermore, a web-based platform developed to facilitate the storage and visualization of data, models, and the representation of damage and impact data following a common metrics approach is presented.

Effects of demand parameters in the performance-based multi-objective optimum design of steel moment frame buildings

This paper investigates the effects of various demand parameters involved in the optimal performance-based design of steel moment frame buildings. These parameters include the peak values of story drift ratio, floor velocity, floor acceleration, and residual drift ratio. The performance-based design is performed to minimize two conflicting objectives, including the initial construction cost and the expected annual repair cost of the building under the design constraints. FEMA P-58 is utilized as a comprehensive and popular methodology for seismic risk assessment and building loss estimation in this paper. It evaluates the building performance in a probabilistic manner in terms of several metrics such as repair cost, repair time, carbon emissions, embodied energy, injuries, and fatalities. The Monte Carlo analysis is used to consider various uncertainties affecting seismic performance. A set of three steel moment-resisting frame (MRF) buildings representative of low-to mid-rise frames are selected as a case study in this research. The results of this study indicate that the story drift ratio has a major role in the performance-based optimal design of steel MRFs. Accordingly, despite increasing the two parameters of floor acceleration and floor velocity due to increasing the initial cost of structural moment frames, the annual repair cost of the building decreases when the story drift ratio decreases.

Main Features of the New Methodology for Seismic Risk Assessment of Armenian Cities

A new methodology for assessment seismic risk of the territory cities of Armenia with a population of up to 50 000 people was developed. The methodology assesses the most important components of the city’s seismic risk: damage of buildings, engineering and transport infrastructure, human and material losses, the risk of some secondary consequences of an earthquake, etc. The methodology widely uses statistical data on the consequences of the 1988 Spitak earthquake and analysis of the causes of these consequences. This article presents the main features of this methodology, which increase the reliability of the evaluation results of especially poorly constructed buildings. A large place is also given to the factual data on the vulnerability of buildings and lifelines, which can be useful in assessing seismic risk in the territories of cities of Armenia and other countries. Examples of evaluating the various risk components obtained as a result of applying the developed technique are presented.

Seismic Risk of Modern City

Aim:The goal of the work was to develop and implement a methodology for the expected seismic risk assessment of a modern city on the example of a test area of Vladikavkaz city.Background:The selected area is characterized by a variety of soil conditions typical for the entire territory of the city. At the same time, building stock includes almost all types of buildings that form the urban environment.Objective:Based on the differentiation of soil conditions, the test area was conditionally divided into 6 sites. Further, site effects of every site were estimated (seismic microzonation work was carried out). Expected seismic intensity (MSK-64) of the sites varied within 7-9 points. Each type of building is characterized by a certain vulnerability to a particular level of seismic impact.Method:The work is focused on the implementation of simple and effective statistical concepts of the MSK-64 scale for the development of express seismic risk assessment methodology. Different soils and types of buildings in different combination caused a different level of expected economic losses. Further, on the basis of taking into account the expected damage in the building stock of Kuybyshev Street, the expected social losses were calculated. In this regard, it is of interest to analyze the seismic risk variations along Kuybyshev Street, which is actually a model of the city.Conclusion:The suggested methodology gives a rapid express assessment of seismic risk for decision making on buildings enforcement on a city level. Seismic risk methodology was corrected for new types of buildings (“Vesna” region) and it was shown that the MSK scale is effective but must be also actualized itself.

DEVELOPMENT OF A UNIFIED MODEL OF GEOINFORMATION SYSTEM FOR CITY PLANNING AND INTEGRATION

On the basis of modern technologies, an information database of seismicity and seismic riskshas been created in the information system designed for city planning which includes maps of detailedseismic zoning (DSZ) of the Republic of North Ossetia-Alania and the map of seismic microzonation (SMZ)of the territory of Vladikavkaz. Evaluation methods of social and economic losses from possible earthquakesof different intensity are considered and a methodology for seismic risk assessment is developed. Analgorithm for introducing the methodology for seismic risk assessment into information systems designed forcity planning is proposed on their basis. Developed system is easily modernized and is the basis of a modernconstantly updated information database that combines the results of all directions of the city planning for thecities and populated areas of North Ossetia, and it can also include any information that has a spatialreference, which makes it possible to include organically these data to the Federal All-Russian InformationSystem.

Developing Seismic Risk Prediction Functions for Structures

The paper presents the development of a nonlinear static displacement-based methodology for seismic risk assessment and loss estimation of stone masonry building stock of Pakistan. Experimental investigation of one-third scaled model, tested on shake table, is performed in order to obtain lateral strength and drift limits for stone masonry and develop damage scale for performance-based assessment. Prototype buildings are designed respecting the existing building stock and investigated through nonlinear static and dynamic time history analyses. Nonlinear static mechanical models, for both global and local vulnerabilities, are developed for the considered typology which are used to derive analytical structure-dependent fragility functions considering expected sources of uncertainties explicitly in contrary to the conventional procedures. Furthermore, seismic risk assessment is performed for different scenario earthquakes and presented in terms of structure-independent fragility functions to estimate the mean damage ratio, the repair cost as a fraction of replacement cost, and casualties, with the dispersion being quantified, given source-to-site distance and magnitude for an earthquake event. The methodology is tested for seismic risk assessment of the considered typology in recent 2005 Kashmir earthquake, which is reasonably predicted. Future development of the methodology is required with additional experimental tests on rubble stone masonry material in order to increase confidence in future applications.

Seismic Evaluation of A Historical Structure In Kastamonu - Turkey

The Kastomonu province is a seismically active zone. the city has many historical buildings made of stone-masonry. In case of any probable future earthquakes, existing buildings may suffer substantial or heavy damages. In the present study, one of the historical traditional house located in Kastamonu were structurally investigated through probabilistic seismic risk assessment methodology. In the study, the building was modeled by using the Finite Element Modeling (FEM) software, SAP2000. Time history analyses were carried out using 10 different ground motion data on the FEM models. Displacements were interpreted, and the results were displayed graphically and discussed.

System-Level Seismic Risk Assessment Methodology: Application to Reinforced Masonry Buildings with Boundary Elements

AbstractThe development of system-level seismic fragility curves, which describe the probability of building systems reaching different damage states under a given ground motion intensity level, is...

Probabilistic Seismic Risk Assessment for Transportation Network

This paper presents a probabilistic seismic risk assessment methodology developed for Highway Bridge including models for transportation network analysis, hazard estimation, and seismic performance of highway components and evaluation of the economic impact to serve as a tool in the decision process for earthquake disaster management including pre-earthquake and post earthquake actions. This study is focused on the development of a procedure for seismic risk assessment, based on a probabilistic seismic hazard analysis.

Probabilistic Seismic Risk Assessment for Transportation Network

This paper presents a probabilistic seismic risk assessment methodology developed for Highway Bridge including models for transportation network analysis, hazard estimation, and seismic performance of highway components and evaluation of the economic impact to serve as a tool in the decision process for earthquake disaster management including pre-earthquake and post earthquake actions. This study is focused on the development of a procedure for seismic risk assessment, based on a probabilistic seismic hazard analysis.

Methodology for seismic risk assessment for tubular steel wind turbine towers: application to Canadian seismic environment

The seismic response of tubular steel wind turbine towers is of significant concern as they are increasingly being installed in seismic areas and design codes do not clearly address this aspect of design. The seismic hazard is hence assessed for the Canadian seismic environment using implicit finite element analysis and incremental dynamic analysis of a 1.65 MW wind turbine tower. Its behaviour under seismic excitation is evaluated, damage states are defined, and a framework is developed for determining the probability of damage of the tower at varying seismic hazard levels. Results of the implementation of this framework in two Canadian locations are presented herein, where the risk was found to be low for the seismic hazard level prescribed for buildings. However, the design of wind turbine towers is subject to change, and the design spectrum is highly uncertain. Thus, a methodology is outlined to thoroughly investigate the probability of reaching predetermined damage states under any seismic loading conditions for future considerations.

Socioeconomic Clustering in Seismic Risk Assessment of Urban Housing Stock

A seismic risk assessment methodology based on socioeconomic clustering of urban habitat is presented in this paper. In this methodology, the city is divided into different housing clusters based on socioeconomic level of occupants, representing reasonably uniform seismic risk. It makes an efficient utilization of high resolution satellite data and stratified random sample survey to develop the building stock database. Ten different classes of socioeconomic clusters found in Indian cities are defined and 34 model building types (MBTs) prevalent on the Indian subcontinent have been identified and compared with the Medvedev-Sponheuer-Karnik (MSK) scale, European macroseismic scale (EMS), parameterless scale of seismic intensity (PSI), and HAZUS classifications. Lower and upper bound damage probability matrices (DPMs) are estimated, based on the MSK and EMS intensity scales and experience from past earthquakes in India. A case study of Dehradun, a city in the foothills of Himalayas, is presented. The risk estimates using the estimated DPMs have been compared with those obtained using the PSI scale. It has been observed that poorer people are subjected to higher seismic risk, both in terms of casualties and in terms of percent economic losses.

DEVELOPMENT OF SEISMIC RISK ASSESSMENT METHODOLOGY FOR HIGH SPEED RAILWAYS

Methodologies for assessing the seismic risk of a high speed railway system were limited to analysis of fragilities of structures and vibration dynamics of vehicles in the past. A deterministic or scenario based approach assuming a particular devastating earthquake was also used in some methodologies. A seismic risk assessment methodology that can estimate the risk of derailment caused by earthquake is proposed in this study. Among constituent factors, the effectiveness of the seismic early warning system that detects the occurrence of earthquakes before the strong ground motion reaches the line is concerned. This study addresses a formulated method to quantify cost-benefit tradeoffs between gain in safety and false alarms. In addition, an assessment model of consequences in terms of injuries and fatalities in derailment disaster, an approach method for network of Shinkansen, and a graphical user interface are considered as perspective studies.