Publications associées à An Analytical Model for Beam Flexure Modules Based on Timoshenko Beam Theory

The time-domain Cartesian multipole expansion of electromagnetic fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Nicolas Mora Parra, Elias Per Joachim Le Boudec, Emanuela Radici, Chaouki Kasmi

Time-domain solutions of Maxwell’s equations in homogeneous and isotropic media are paramount to studying transient or broadband phenomena. However, analytical solutions are generally unavailable for practical applications, while numerical solutions are co ...

Nature Publishing Group2024

Instabilities in Elastic and Magneto-Elastic Beams and Shells: from Shell Buckling to the Design of a Programmable Braille Reader

Arefeh Abbasi

In this thesis, we conduct a comprehensive investigation into structural instabilities of both elastic and magneto-elastic beams and shells, resulting in a creative proposal to design a programmable braille reader. Methodologically, we combine numerical si ...

EPFL2024

Exploring the potential of the critical shear crack theory for reinforced and post-tensioned glass beams: Initial analysis and experiments

Alain Nussbaumer, Pieter Christian Louter, Jagoda Cupac

In the evolution of structural glass beam elements, the requirements for post-fracture load bearing capacity and safe failure behaviour have led to the development of reinforced and post-tensioned beams. Maximum bending capacity in the post-fracture state ...

2023

Geometric tolerances of welded connections with inelastic panel zones

Dimitrios Lignos, Andronikos Skiadopoulos, Ce Wen

Prequalified beam-to-column connections in steel moment resisting frames usually concentrate inelastic deformations in the steel beam ends. As such, nonlinear geo-metric instabilities (i.e., local buckling) may occur in these regions at modest lateral drif ...

Ernst & Sohn2023

Digital-Image-Correlation for Simulating Cyclic Local Buckling in Steel Beams

Albano António De Abreu E Presa De Castro E Sousa, Dimitrios Lignos, Selimcan Ozden

Nonlinear continuum finite element (CFE) analyses rely on accurate multiaxial constitutive law formulations along with reliable imperfection patterns for simulating nonlinear geometric instabilities in steel members under mechanical loading. Validations of ...

Wiley2023

Full Scale Experiments of a Composite Steel Moment Resisting Frame: Behavioral Insights and Implications on Seismic Design

Dimitrios Lignos, Hammad El Jisr

This paper discusses the cyclic performance of a heavily instrumented 2-bay full-scale composite-steel moment resisting frame (CMRF) sub-system from the onset of structural damage up until incipient collapse. The CMRF featured stiffened end plate bolted co ...

EEME2023

Full-Scale Experiments of Cyclically Loaded Welded Moment Connections with Highly Dissipative Panel Zones and Simplified Weld Details

Dimitrios Lignos, Andronikos Skiadopoulos

This paper presents the experimental results of two welded unreinforced flange-welded web (WUF-W) beam-to-column connections that defy the current design paradigm of prequalified welded connections. The proposed WUF-W connections feature customized beveled ...

2023

Towards instability-free welded moment connections

Dimitrios Lignos, Andronikos Skiadopoulos

In capacity-designed steel moment resisting frames (MRFs), inelastic deformations are mostly concentrated in the steel beams and the column fixed ends of the first story, while the participation of the panel zones in energy dissipation is limited. In such ...

2023

C-shells: Deployable Gridshells with Curved Beams

Mark Pauly, Francis Julian Panetta, Yingying Ren, Quentin Christian Becker, Davide Pellis, Seiichi Eduardo Suzuki Erazo

We introduce a computational pipeline for simulating and designing C-shells, a new class of planar-to-spatial deployable linkage structures. A C-shell is composed of curved flexible beams connected at rotational joints that can be assembled in a stress-fre ...

2023

Analytical modeling and experimental validation of rotationally actuated pinned–pinned and fixed–pinned buckled beam bistable mechanisms

Simon Nessim Henein, Etienne Frédéric Gabriel Thalmann, Loïc Benoît Tissot-Daguette, Hubert Pierre-Marie Benoît Schneegans

Buckled beams have become key building blocks in compliant mechanisms to achieve nonlinear behaviors, such as bistability, constant-force and stiffness tuning. However, designing and modeling such components is challenging due to their highly nonlinear cha ...

2022

Full-scale testing of European steel beams with reduced beam section under reversed cyclic loading

Dimitrios Lignos, Hiroyuki Inamasu

Steel beams with reduced beam section (RBS) are often used as part of prequalified connections in seismic regions. However, RBS connections are not as common in Europe. Reasons relate to easiness in fabrication, which requires on-site welding, and the seis ...

Springer Nature2022

Differential Entropy of the Conditional Expectation Under Additive Gaussian Noise

Michael Christoph Gastpar, Alper Köse, Ahmet Arda Atalik

The conditional mean is a fundamental and important quantity whose applications include the theories of estimation and rate-distortion. It is also notoriously difficult to work with. This paper establishes novel bounds on the differential entropy of the co ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Warping-Inclusive Kinematic Coupling in Mixed-Dimension Macro Models for Steel Wide Flange Beam Columns

Albano António De Abreu E Presa De Castro E Sousa, Dimitrios Lignos, Alexander Riley Hartloper

A warping-inclusive kinematic coupling method to be used in finite-element analysis of members featuring wide-flange cross sections is proposed in this paper. This coupling method is used in mixed-dimension macromodels that combine continuum and beam-colum ...

2022

Seismic stability of steel moment resisting frames with inelastic panel zones

Dimitrios Lignos, Andronikos Skiadopoulos

This paper summarizes preliminary findings of nonlinear simulations aiming to quantify the seismic demands of codecompliant steel MRFs with variable panel zone targeted shear distortions, 𝛾!. The probability of beam fractures is explicitly considered in th ...

Earthquake Engineering Research Institute2022

A comprehensive framework for hard-magnetic beams: Reduced-order theory, 3D simulations, and experiments

Pedro Miguel Nunes Pereira de Almeida Reis, Dong Yan, Arefeh Abbasi

Thin beams made of magnetorheological elastomers embedded with hard-magnetic particles (hard-MREs) are capable of large deflections under an applied magnetic field. We propose a comprehensive framework, comprising a beam model and 3D finite element modelin ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Welded moment connections with highly dissipative panel zones for enhanced seismic performance of steel moment frames

Andronikos Skiadopoulos

Research conducted after the 1994 Northridge earthquake in the U.S. and the 1995 Kobe earthquake in Japan led to the development of today's pre-qualified beam-to-column connections for capacity-designed steel moment resisting frames (MRFs). Welded moment c ...

EPFL2022

The Role of the Composite Floor System and Framing Action in the Seismic Performance of Composite Steel Moment-Resisting Frames

Hammad El Jisr

With the advent of performance-based earthquake engineering (PBEE), the need for reliable prediction of earthquake-induced collapse of structures is essential. Despite the significant progress that has been made towards this goal, there are several hurdles ...

EPFL2022

Design of slender and squat reinforced concrete members with shear reinforcement

Aurelio Muttoni, Miguel Fernández Ruiz, Marko Pejatovic

As proposed in several design standards for structural concrete, including Eurocode 2 (EN:1992-1-1:2004) and fib's Model Code 2010, the shear design of slender members with shear reinforcement can be performed by means of consistent models based on suitabl ...

ERNST & SOHN2022

Load cell with adjustable stiffness based on a preloaded T-shaped flexure pivot

Simon Nessim Henein, Charles Baur, Loïc Benoît Tissot-Daguette, Michal Stanislaw Smreczak

In this paper, we present a new flexure-based load cell with adjustable stiffness designed for force sensors with extended force range and respective measuring resolution. This novel monolithic mechanism consists of a T-shaped flexure pivot combined with a ...

euspen2021

Hysteretic Behaviour of Shear Stud Connectors in Composite Steel Moment‐Resisting Frames

Dimitrios Lignos, Hammad El Jisr

In steel moment resisting frames (MRFs) with composite floor slabs, seismic loads are transmitted from the slab into the beam through shear studs. Shear strength degradation of the studs due to cyclic loading results into the loss of the load transfer mech ...

2021