Nikola Blagojević

Last Name

Blagojević

First Name

Nikola

ORCID

0000-0002-1887-1037

Show all metadata

Search Results

Publications 1 - 10 of 35

Supply/demand interface for disaster resilience assessment of interdependent infrastructure systems considering privacy and security concerns
Blagojević, Nikola; Stojadinovic, Bozidar (2023)
Environment Systems & Decisions
The ability to swiftly restore functionality following an extreme event is an essential characteristic of a disaster resilient infrastructure system. However, the restoration of functionality of a single infrastructure system often depends on the functionality of other systems that provide resources the considered system needs to operate and recover. Furthermore, infrastructure systems are crucial for the post-disaster functional recovery of the building stock of a community. Thus, community resilience assessment and improvement require a system-of-systems perspective, considering the post-disaster performance of several interdependent infrastructure systems and the building stock at the same time. One of the principal issues in resilience assessment and improvement is that such system-of-systems consideration may require detailed information on the vulnerability and recoverability of numerous components. While such information might be available for certain systems (e.g., housing), for others, the information might be unavailable due to privacy and security concerns (e.g., electric power supply systems or buildings housing important functions). In this paper, we propose a supply/demand interface between the system-of-systems simulator, defined within the interdependent Resilience - Compositional Demand/Supply (iRe-CoDeS) framework, and the individual infrastructure system simulators. Such an interface can be used for regional recovery simulation and resilience assessment of interdependent infrastructure systems, while allowing infrastructure system operators to maintain system’s privacy and/or security. We define a tiered supply/demand interface, where the amount of information provided by individual systems can range from system-level to component-level post-disaster evolution of resource supply and demand, assessed using expert opinion or confidential in-house models. The proposed supply/demand interfaces are illustrated in a semi-virtual case study, assessing the seismic resilience of North-East San Francisco, focusing on the effect of interdependent infrastructure on the functional recovery of residential buildings.
Evaluating the Importance of Interdependent Civil Infrastructure System Components for Disaster Resilience of Community Housing
Blagojević, Nikola; Lauber, Nathalie; Didier, Max; et al. (2022)
Lifelines 2022: 1971 San Fernando Earthquake and Lifeline Infrastructure
Housing disaster resilience is crucial for community disaster resilience as it provides two essential functions: shelter from the elements and functional housing. We present a methodology to quantify community housing disaster resilience considering the unmet post-disaster community demand for both shelter and functional housing. Total Sobol indices are used to evaluate the importance of the vulnerability and recoverability of individual components of community infrastructure systems and building stock units for community housing disaster resilience, while requiring no prior knowledge of these component properties. We illustrate the application of the proposed importance analysis on a virtual community considering the functionality of the electric power supply, water supply and communication infrastructure systems, and a number of building stock units.
Decoding humanitarian programs complexity via systems thinking: unveiling critical infrastructure-to-system causal loops
Celentano, Giulia; Marmo, Rossella; Blagojević, Nikola; et al. (2025)
SBE Conference Series ~ Sustainable Built Environment Conference 2025 Zurich - Extended Abstracts
Towards a dynamic earthquake risk framework for Switzerland
Böse, Maren; Danciu, Laurentiu; Papadopoulos, Athanasios N.; et al. (2024)
Natural Hazards and Earth System Sciences
Scientists from different disciplines at ETH Zurich are developing a dynamic, harmonised, and user-centred earthquake risk framework for Switzerland, relying on a continuously evolving earthquake catalogue generated by the Swiss Seismological Service (SED) using the national seismic networks. This framework uses all available information to assess seismic risk at various stages and facilitates widespread dissemination and communication of the resulting information. Earthquake risk products and services include operational earthquake (loss) forecasting (OE(L)F), earthquake early warning (EEW), ShakeMaps, rapid impact assessment (RIA), structural health monitoring (SHM), and recovery and rebuilding efforts (RRE). Standardisation of products and workflows across various applications is essential for achieving broad adoption, universal recognition, and maximum synergies. In the Swiss dynamic earthquake risk framework, the harmonisation of products into seamless solutions that access the same databases, workflows, and software is a crucial component. A user-centred approach utilising quantitative and qualitative social science tools like online surveys and focus groups is a significant innovation featured in all products and services. Here we report on the key considerations and developments of the framework and its components. This paper may serve as a reference guide for other countries wishing to establish similar services for seismic risk reduction.
Residential building stock in Serbia: classification and vulnerability for seismic risk studies
Blagojević, Nikola; Brzev, Svetlana; Petrovic, Milica; et al. (2023)
Bulletin of Earthquake Engineering
Regional seismic risk assessment is necessary for designing effective seismic risk mitigation measures. In general, such risk assessment studies consist of three components: hazard, vulnerability, and exposure modelling. This paper lays the foundations for regional seismic risk assessment of the residential building stock in Serbia and addresses each of the three seismic risk assessment components, either by reviewing the existing or proposing novel models. First, a review of seismic hazard models and seismic design codes used in Serbia in the past 70 years was presented. Next, an overview of Serbia's population metrics and historical development of Serbian's residential building stock was presented to provide the context for the exposure model. Furthermore, the paper proposed a novel building classification for Serbia's residential building stock, which is based on the existing building taxonomies, but it has been adapted to account for the local building characteristics. Building damage patterns reported in past earthquakes in Serbia and neighbouring countries were reviewed as a basis for damage classification pertaining to building typologies included in the proposed classification. Finally, the results of a preliminary vulnerability model were presented in the form of expert-based fragility functions derived for buildings typical of Serbia's residential building stock.
Out-of-plane behaviour of loadbearing and non-structural masonry walls during recent earthquakes
Marinković, Marko; Brzev, Svetlana; Baballëku, Markel; et al. (2021)
Conference Proceedings from 1st Croatian Conference on Earthquake Engineering - 1CroCEE
Recent earthquakes in Balkan, including the September 21 and November 26, 2020 Albania earthquakes, March 22, 2020 Zagreb earthquake, and the December 29, 2020 Petrinja, Croatia earthquakes had devastating consequences for the affected population of these countries. Besides substantial structural damage of RC buildings as well as loadbearing masonry buildings, these earthquakes caused significant damage of non-structural masonry elements. This paper presents examples of the damage for loadbearing and non-structural masonry walls (infills and partitions) due to out-of-plane seismic effects, as observed by the authors during the reconnaissance visits to the affected areas. This type of damage can prevent the evacuation of people from the buildings during the earthquake, as the falling masonry elements block the evacuation routes, and hinder the reoccupancy and functional recovery of affected buildings after an earthquake. The authors recognize that both loadbearing and non-structural walls (infills and partitions) experienced out-of-plane collapse due to lack of connection to the floor/frame. Using the examples of the damage or failure of masonry walls during the recent earthquakes, their failure mechanisms were explained and the lessons learned were summarized in the paper.
Extending National Seismic Risk Models to Assess Regional Recovery Capabilities and Community Resilience: Case Study - Basel, Switzerland
Blagojević, Nikola; Papadopoulos, Athanasios N.; Danciu, Laurentiu; et al. (2024)
Seismic risk assessment on a regional scale is essential for informing the development and implementation of seismic risk reduction measures. However, most of the existing seismic risk models focus on the direct losses (i.e., casualties and repair costs), without in-depth considerations of the indirect losses caused by the downtime of buildings and interdependent infrastructure following seismic events. Such considerations are necessary to assess and increase community resilience by informing post-earthquake recovery plans and estimating resources needed for reconstruction. We present recent preliminary efforts to extend the existing national seismic risk models to simulate regional recovery and assess resilience. Such an extension of seismic risk models allows for the assessment of recovery capabilities of communities and their expected indirect losses, as well as for the development of informed regional recovery plans, increasing community disaster preparedness. An extension of the Earthquake Risk Model of Switzerland using the iRe CoDeS framework is presented and illustrated by simulating recovery of a neighborhood in Basel, Switzerland, following a scenario earthquake.
Performance of RC cast-in-place buildings during the November 26, 2019 Albania earthquake
Marinković, Marko; Baballëku, Markel; Isufi, Brisid; et al. (2022)
Bulletin of Earthquake Engineering
This paper documents performance of cast-in-place reinforced concrete (RC) buildings in the Durres municipality during Albania earthquake of November 26, 2019 (M-W 6.4). Both mid- and high-rise RC buildings were affected by the earthquake, experiencing structural and/or non-structural damage and even collapse in some cases. The authors performed a reconnaissance study after the earthquake and were involved in seismic assessment of buildings in the affected area. Besides the observations related to physical damage of RC buildings, the paper also presents results of a statistical analysis of damaged RC buildings in the Durres municipality. The discussion in the paper is focused on damage patterns and failure mechanisms that are relevant for the seismic response of RC structures. Most common damage pattern observed after the earthquakes was related to masonry infill walls, which experienced damage and failure in some cases, and affected the performance of adjacent RC columns due to the infill/frame interaction. Taller RC framed buildings (10 storeys and higher) were expected to have RC shear walls; however, these walls were reportedly absent in the damaged buildings of this type. In some cases, masonry infill walls (instead of RC shear walls) were used in the elevator shaft areas, which resulted in inadequate seismic performance. A case study has been presented to illustrate seismic behaviour of mid-rise and high-rise cast-in-place RC buildings in the November 2019 earthquake, and is based on post-earthquake field observations and a detailed seismic assessment of two earthquake-damaged buildings. Finally, relevant lessons and recommendations are presented in light of the observed performance of RC buildings.
Capturing Regional Aspects of Building's Functional Recovery Using the F-RECN + iRe-CoDeS Framework
Blagojević, Nikola; Terzić, Vesna; Stojadinovic, Bozidar (2024)
Significant indirect losses caused by long recovery times of the building stock following recent earthquakes have motivated the earthquake engineering research community to consider functional recovery as an additional building performance objective. Designing for functional recovery aims to minimize the time that a building needs to achieve functionality following an earthquake. To implement building design that includes the functional recovery performance objective in engineering practice, new functionality-oriented provisions are needed in seismic design codes, and new modelling and analysis tools are needed to assess if such code-specified requirements are satisfied. However, a major obstacle is the fact that functional recovery of a single building does not only depend on the performance of that building alone, as is the case for the life safety and collapse-prevention performance objectives. The functional recovery of a single building is affected by the post-earthquake state of interdependent lifelines as well as the state of the regional building stock: the supply of recovery resources (e.g., workforce, building material, machinery) can be strained due to a high post earthquake demand dictated by the regional building damage. We present an extension of the F-RecN + iRe CoDeS framework to include the impact of lifelines and regional resource constraints on building’s functional recovery. The F-RecN + iRe-CoDeS framework captures the impact of resource constraints by integrating the regional recovery model developed in the iRe-CoDeS framework with a detailed building-component-level F Rec recovery model for each building in the considered region. The regional iRe-CoDeS model distributes the available resources to buildings, while the building-level F-Rec model recovers only those building components whose resource demand is met at a time step of the recovery simulation. Such an integrated regional building stock model is further extended to capture the impact of interdependent lifelines on buildings’ functional recovery by coupling third-party lifeline models with the building stock model using supply/demand interfaces. The aim of the presented framework is to enable the next-generation functionality-oriented seismic design code provisions while capturing the regional aspect of building’s functional recovery. The extended F-RecN + iRe-CoDeS framework is illustrated by assessing functional recovery of a virtual building stock characteristic of downtown Los Angeles.
A Framework for Probabilistic Resilience-based Assessment and Design of the Built Environment
Blagojević, Nikola (2023)

Publications 1 - 10 of 35

Nikola Blagojević

Last Name

First Name

ORCID

Organisational unit

Filters

Search Results