Publications associées à The seismic stability and ductility of steel columns interacting with concrete footings

Shear and steel-fibre reinforcement for the punching resistance of flat slabs at internal and edge columns

Reinforced concrete flat slabs consist of a continuous, thin concrete plate that rests on a grid of columns. The supporting surface of the columns is very small compared to the floor plan dimensions, leading to concentrations of shear forces near the colum ...

EPFL2024

A Softening Constitutive Law and Gradient-Inelastic Fiber-Based Element for 3-Dimensional Frame Simulations Under Seismic Excitations

Diego Isidoro Heredia Rosa

Steel frame structures are essential components of modern infrastructure. Understanding their behavior under seismic loading is critical for ensuring public safety and minimizing damage that occurs during earthquakes. To accurately predict the response of ...

EPFL2024

Influence of model uncertainty and long term deformations in action effects calculation in reinforced concrete structures

Xhemsi Malja

Most codes of practice adopt a semi probabilistic design approach for the dimensioning and assessment of structures. Accordingly, structural safety is ensured by performing limit state verifications using design values determined with adequately calibrated ...

EPFL2024

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

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

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

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

How roughness emerges on natural and engineered surfaces

Jean-François Molinari, Ramin Aghababaei

Roughness, defined as unevenness of material surfaces, plays an important role in determining how engineering components or natural objects interact with other bodies and their environment. The emergence of fractal roughness on natural and engineered surfa ...

SPRINGER HEIDELBERG2023

Dissipative Embedded Column Bases for Enhanced Seismic Performance of Steel Moment Resisting Frames

Albano António De Abreu E Presa De Castro E Sousa, Dimitrios Lignos, Hiroyuki Inamasu

This paper presents an innovative design concept for embedded column base (ECB) connections. The developed ECB connection achieves a non-degrading hysteretic response. In the proposed ECB connections, the dissipative zone is shifted into the embedded porti ...

EEME2023

The new Chapter 9 of Eurocode 8 Part 3 for Seismic Assessment of Existing Steel Structures

Dimitrios Lignos

The seismic assessment of existing steel structures necessitates the development of practice- oriented engineering models for use in nonlinear static and dynamic analysis procedures. These models should encompass the full range of the anticipated nonlinear ...

2023

Hysteretic behaviour of welded connections with highly inelastic panel zones

Dimitrios Lignos, Andronikos Skiadopoulos

The current practice in capacity-designed steel moment resisting frames (MRFs) worldwide allows for limitedshear yielding in the column web panel zone. As such, inelastic deformations concentrate near the beam ends, thereby leading to flexural stre ...

Ernst & Sohn2023

Diffusion of energy technologies: the role and dynamics of supply-side information networks

Claudia Rebeca Binder Signer, Romano Tobias Wyss, Gloria Serra Coch, Maria Anna Hecher

The diffusion of energy technologies is key for supporting the energy transition. While social influence and peer effects have been extensively studied on the demand side and found to impact adoption, less focus has been given to the role of information ne ...

2023

Energy dissipation in fiber-polymer composites adhesive joints under cyclic loading

Ghazaleh Eslami

Sustainable development has emerged as a paramount consideration in various fields of industry, including construction, to preserve the environment and its finite resources. Lightweight structures, such as fiber-polymer composite structures, address both s ...

EPFL2023

Proposed Panel Zone Model for Beam-To-Column Joints in Steel Moment Resisting Frames

Dimitrios Lignos, Ahmed Mohamed Ahmed Elkady, Andronikos Skiadopoulos

In capacity designed steel moment resisting frames (MRFs), beam-to-column joints (i.e., panel zones) are designed to remain elastic. To potentially exploit the beneficial aspects of the stable panel zone hysteretic response in shear, a robust panel zone mo ...

2023

Caching and Neutrality

Aikaterini Argyraki, Pavlos Nikolopoulos, Muhammad Abdullah

We are used to defining network neutrality as absence of traffic differentiation, like policing or shaping. These mechanisms, however, are often not what determines end-users’ quality of experience (QoE). Most content today is accessed through edge caches, ...

ACM Association for Computing Machinery2023

Experimental Investigation of Instability-Free Welded Moment Connections With Simplified Weld Details

Dimitrios Lignos, Andronikos Skiadopoulos

In capacity designed steel moment resisting frames, inelastic deformations are mostly concentrated in the steel beams and the column fixed ends of the first story. This design concept limits the participation of the column web’s panel zone in the energy di ...

2023

Deformation capacity evaluation for flat slab seismic design

Aurelio Muttoni, António Manuel Pinho Ramos, Lorenzo Martinelli, Andri Setiawan

In flat-slab frames, which are typically designed as secondary seismic structures, the shear failure of the slab around the column (punching failure) is typically the governing failure mode which limits the deformation capacity and can potentially lead to ...

SPRINGER2022

Seismic Performance of Strengthened Slab-Column Connections in a Full-Scale Test

Aurelio Muttoni, António Manuel Pinho Ramos

Strengthening of flat slab-column connections to resist imposed lateral drifts is often required for older reinforced concrete structures in which the flat slabs were typically designed to resist gravity load only or have been designed for less stringent r ...

TAYLOR & FRANCIS LTD2022

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

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