Publications associées à Deriving fragility functions from bilinearized capacity curves for earthquake scenario modelling using the conditional spectrum

Climate risk assessment of buildings: An analysis of operating emissions of commercial offices in Australia

Building climate risk assessment involves benchmarking a building's energy use intensity against decarbonisation pathways to mitigate the impacts on climate change. Various climate risk assessment tools and frameworks are used for commercial buildings in d ...

Elsevier Science Sa2024

The use of ductile steel fuses for the seismic protection of acceleration sensitive non- structural components: Numerical and Experimental verification

Dimitrios Lignos, Ahmed Mohamed Ahmed Elkady

Recent seismic events have showcased the vulnerability of non-structural components to even low- or moderate-intensity earthquakes that occur far more frequently than design-basis ones. Thus, community-critical buildings, such as hospitals, telecommunicati ...

EEME2023

Numerical and experimental investigation of spiral-grooved gas journal bearings

Elia Iseli

Small-scale turbomachinery is increasingly used in carbon-free energy conversion systems, such as commercial or domestic scale heat pumps, fuels cells for transportation and waste heat recovery. The usage of aerodynamic bearings allows the design of compac ...

EPFL2022

Fragility Assessment of Beam-Slab Connections for Informing Earthquake-Induced Repairs in Composite-Steel Moment Resisting Frames

Dimitrios Lignos, Hammad El Jisr

Earthquake loss estimation in composite-steel moment resisting frames (MRFs) necessitates a proper estimation of the level of damage in steel beam-to-slab connections. These usually feature welded headed shear studs to ensure the composite action between t ...

2021

Uncertainties in the Seismic Assessment of Historical Masonry Buildings

Katrin Beyer, Francesco Vanin, Igor Tomic

Seismic assessments of historical masonry buildings are affected by several sources of epistemic uncertainty. These are mainly the material and the modelling parameters and the displacement capacity of the elements. Additional sources of uncertainty lie in ...

2021

Time-delay Cosmography with Strongly Lensed Quasars

Martin Raoul Robert Millon

The LCDM model has emerged as the concordance model of cosmology for its ability to explain a variety of observations, ranging from the anisotropies of the Cosmic Microwave Background (CMB) to the accelerated expansion of the Universe. However, with the ev ...

EPFL2021

Seismic Behavior of Pine Flat Concrete Gravity Dam Using Microplane Damage-Plasticity Model

Giovanni De Cesare, Pedro Filipe De Almeida Manso, Samuel Luke Vorlet

The response of concrete gravity dams under seismic loads is a major concern of dam safety assessment in earthquake-prone areas. This study focuses on the seismic analysis of the tallest non-overflow monolith of Pine Flat Dam. The paper presents results of ...

Springer, Cham2020

Inverse Analysis of Radiative Flux Maps for the Characterization of High Flux Sources

Sophia Haussener, Gaël Jean Clément Levêque, Clemens Gregor Suter

The reconstruction of the angular and spatial intensity distribution from radiative flux maps measured in high flux solar simulators or optical concentrators is an ill-posed inverse problem requiring special solution strategies. We aimed at providing a sol ...

2019

Quantifying the out-of-plane response of unreinforced masonry walls subjected to relative support motion

Katrin Beyer, Michele Godio

The supports of out-of-plane loaded unreinforced masonry walls in buildings are subjected to a motion that is filtered and amplified by the building structure and, in some cases, can be significantly different from the ground motion. Moreover, because thes ...

2019

Experimental investigation of steel building gravity framing systems under strong earthquake shaking

Dimitrios Lignos

Hybrid simulations were conducted to evaluate the system-level seismic response of a 4-story steel moment frame building and its gravity framing system through various levels of ground motion shaking. The experimental substructure examined in detail corres ...

2019

Phase resolved characterization of nanoscale features in optical microstructures

Michail Symeonidis

In this study, we apply interferometric microscopy to study the phase, alongside the intensity, of the light field transmitted through a wide variety of samples. Additionally, we conduct those interferometric measurements at different wavelengths within th ...

EPFL2019

Fragility Curves for Wide-Flange Steel Columns and Implications on Building-Specific Earthquake-Induced Loss Assessment

Dimitrios Lignos, Ahmed Mohamed Ahmed Elkady, Subash Ghimire

Building-specific loss assessment methodologies utilize component fragility curves to compute the expected losses in the aftermath of earthquakes. Such curves are not available for steel columns assuming they remain elastic due to capacity design considera ...

2018

Earthquake-Induced Collapse Risk and Loss Assessment of Steel Concentrically Braced Frames

Dimitrios Lignos, Seong-Hoon Hwang

This paper quantifies the collapse risk and earthquake-induced losses for a wide range of archetype buildings with special concentrically braced frames (SCBFs). The collapse risk and expected economic losses associated with repair, demolition and collapse ...

2018

Earthquake-Induced Collapse Risk and Loss Assessment of Steel Concentrically Braced Frames

Dimitrios Lignos, Seong-Hoon Hwang

This paper quantifies the collapse risk and earthquake-induced losses for a wide range of archetype buildings with special concentrically braced frames (SCBFs). The collapse risk and expected economic losses associated with repair, demolition and collapse ...

2018

Seismic retrofit of steel tall buildings with bilinear oil dampers

Dimitrios Lignos

This paper presents retrofit solutions for existing tall buildings by utilizing supplemental damping devices, namely oil dampers with relief valve (bilinear oil dampers). To this end, multiple retrofit schemes are presented for a benchmark 40-story steel m ...

2018

Evaluation of the seismic retrofitting of an unreinforced masonry building using numerical modeling and ambient vibration measurements

Pierino Lestuzzi, Clotaire Michel, Amin Karbassi

Ambient vibration measurements and 3-D nonlinear time-history numerical modeling are used to assess the retrofitting measures conducted in a 6-story unreinforced masonry building (URM) built in the end of the 19th century in Switzerland. Retrofitting measu ...

2018

Nonmodel-based framework for rapid seismic risk and loss assessment of instrumented steel buildings

Dimitrios Lignos, Seong-Hoon Hwang

This paper proposes a nonmodel-based framework for estimating story-based engineering demand parameters (EDPs) in instrumented steel frame buildings with steel moment-resisting frames (MRFs). The proposed framework utilizes a wavelet-based damage-sensitive ...

Elsevier2018

Assessment of structural damage detection methods for steel structures using full-scale experimental data and nonlinear analysis

Dimitrios Lignos, Seong-Hoon Hwang

Rapid structural damage assessment methodologies are essential to properly allocate emergency response and minimize business interruption due to downtime in the aftermath of earthquakes. Within this context, data-driven algorithms supported by sensing capa ...

2018

Assessment of the Probability of Collapse of Structures Under Earthquakes

Dimitrios Lignos

Avoidance of collapse is the most important objective in earthquake resistant design, but assessing the probability of collapse of a structure during an earthquake is technically challenging and it is computationally demanding. This paper summarizes recent ...

International Association of Earthquake Engineering2017

Effect of Modeling Assumptions on the Earthquake-Induced Losses and Collapse Risk of Steel-Frame Buildings with Special Concentrically Braced Frames

Dimitrios Lignos, Seong-Hoon Hwang

This paper quantifies the collapse risk and earthquake-induced economic losses of steel-frame buildings with special concentrically braced frames designed in urban California. A probabilistic building-specific loss estimation methodology that can explicitl ...

Asce-Amer Soc Civil Engineers2017