Publications associées à New experimental determination of fatigue strength of tubular truss joints in steel grades up to S690

Strain-based analysis on the influence of local undercut geometry on fatigue crack initiation life

Alain Nussbaumer, Heikki Tapani Remes, Abinab Niraula

The local undercut defects at the weld toe provide a potential initiation site for fatigue cracks and significantly impact the structure's fatigue strength. The influence of continuous undercut depth on fatigue performance is widely studied, but the resear ...

2024

FLO:RE – A new floor system made of reused reinforced concrete and steel elements

Maléna Bastien Masse, Numa Joy Bertola, Célia Marine Küpfer, Corentin Jean Dominique Fivet

Carefully extracting reinforced concrete (RC) elements from soon-to-be demolished structures and reusing them as load-bearing components is an emerging circular low-carbon alternative to building new structures. As floor construction typically accounts for ...

IABSE2024

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

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

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

Proposed residual stress model for hot‐rolled wide flange steel cross sections

Albano António De Abreu E Presa De Castro E Sousa, Dimitrios Lignos, Andronikos Skiadopoulos

Residual stresses in hot-rolled wide flange steel cross sections may lead to premature yielding, accelerated corrosion and brittle fracture of steel members. The above phenomena lead to a loss of a steel member's stiffness and resistance under mechanical l ...

Ernst & Sohn2023

Microscopic Digital Image Correlation Analysis of Strain Distributions in Stainless Steel 316L Induced by Multiaxial Cyclic Loading

Elif Cansu Kursun

Fatigue damage in materials results in localized strain at the microstructural level. In many engineering components of the cooling circuits of nuclear power plants, where austenitic steels are used, the material experiences multiaxial cyclic loading, eith ...

EPFL2023

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

Experimental Evaluation and Modeling of Residual Stress Distributions for Hot-Rolled Wide Flange Steel Members

Albano António De Abreu E Presa De Castro E Sousa, Dimitrios Lignos, Andronikos Skiadopoulos

Local and member instability modes in structural steel members are influenced by initial geometric imperfections and residual stresses among other parameters. The robustness of stability-related design provisions and finite element modeling procedures of s ...

2023

Hydro-mechanichal characterisation of bentonite/steel interfaces

Alessio Ferrari, Eleni Stavropoulou, Fabiana Sannasardo

The hydromechanical response of a Wyoming-type bentonite (MX-80) and its interface with steel was studied in terms of shear resistance under different hydration levels. A series of shear tests under constant normal stress were performed in total suction co ...

2023

Thermal Modelling and Experimental Validation in the Perspective of Tool Steel Laser Polishing

Alexandre Masserey, Eric Boillat, Bastian Meylan

Laser polishing (LP) is a process that allows a significant reduction of the surface roughness of a metal workpiece via re-melting a shallow layer of material. However, the practical use of LP is limited due to the difficulty of satisfying the high surface ...

MDPI2022

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

Experimental Investigation of the Inelastic Cyclic Behavior of Concrete-Filled Double-Skin Tubular Beam-Columns with Corrugated Inner Skins and Ultrahigh-Strength Corner Tubes

Mojtaba Farahi, Dimitrios Lignos

This paper presents the experimental results from nine full-scale concrete-filled double-skin tubular (CFDST) beam-columns. The test specimens exploited two fabrication strategies, featuring either hollow steel inner skins with corrugated geometry or ultra ...

ASCE-AMER SOC CIVIL ENGINEERS2022

Experimental investigation of dowel action using advanced measurement techniques

Aurelio Muttoni, Marko Pejatovic

Existing shear-cracked structures need to be reliably verified in order to avoid redundant interventions. Code provisions often raise shear safety and/or fatigue life concerns of the reinforcement subjected to stress concentrations due to cyclic dowel acti ...

2022

Strong silicon oxide inclusions in iron

Andreas Mortensen, Léa Deillon, Alejandra Inés Slagter, Joris Pierre Everaerts

Oxide inclusions are ubiquitous in steel and are known to affect, generally in a negative sense, the mechanical performance of steel products. Micromechanical properties of those phases are therefore important, yet they have remained largely unexplored. We ...

2022

Long anchorage resistance of reinforcement bars derived from local bond-slip relationships for good and poor bond conditions

Aurelio Muttoni, Enrique Corres Sojo

The fib Model Code 2010 (MC2010) contains a semi-empirical formulation for the local bond-slip relationship for both pull-out and splitting failure modes (derived from short pull-out tests), as well as a semi-empirical formulation of the steel stress that ...

2022

APT/TEM characterization of the element segregation in ferritic/martensitic steels after irradiation in SINQ

Lijuan Cui

Ferritic /martensitic (FM) steels are among the most important materials in various nuclear applications. As radiation-induced segregation (RIS) is one of the major factors for embrittlement of nuclear materials, thereofre it is essential to study the RIS ...

EPFL2021

Cyclic metal plasticity model parameters with limited information: a constrained optimization approach

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

Tensile test data for structural steels are ubiquitous. Yet, the information monotonic loading provides with respect to the material's characteristics is limited. Notably, features of inelastic response to cyclic loading, such as the Bauschinger eect, can ...

2021

Enhancement of riveted steel bridges by adding a trough in UHPFRC acting in composite action

Eugen Brühwiler

Riveted railway bridges are commonly considered as being “old”, having fatigue damage and are therefore replaced. While this practice should be by now obsolete by using novel engineering methods like structural monitoring, prolongation of the service durat ...

Taylor & Francis2021

Reduced-order Models for Simulating Coupled Geometric Instabilities in Steel Beam-columns Under Inelastic Cyclic Straining

Alexander Riley Hartloper

Numerical models that can simulate coupled geometric instabilities in steel beam-columns are required for the seismic assessment of certain steel moment-resisting frames. Reliably simulating coupled instabilities requires that the steel material is precise ...

EPFL2021