Publications related to New framework for calibration of partial safety factors for fatigue design

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

Influence of fiber orientation on the tensile behavior of UHPFRC and reinforced UHPFRC under static and fatigue loadings

Jian Zhan

Ultra-high performance fiber reinforced cementitious composite (UHPFRC) is a modern class of cementitious building materials. Because of its superior mechanical properties and durability, it is increasingly used globally to rehabilitate, strengthen and mod ...

EPFL2024

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

Probabilistic fatigue model for composites based on the statistical characteristics of the cycles to failure

Anastasios Vassilopoulos, Guangjian Xiang

A probabilistic model for estimating the fatigue life of composite laminates based on the mean value and standard deviation of the fatigue life is introduced here for predicting the distribution of fatigue life at any stress level for a constant stress rat ...

ELSEVIER SCI LTD2022

Fatigue resistance of reinforced UHPFRC beams

Eugen Brühwiler, Bartlomiej Wojciech Sawicki

This work investigates the fatigue resistance of reinforced Ultra High Performance Fiber Reinforced Cementitious composite (R-UHPFRC) beams with special consideration of steel rebar – UHPFRC interaction under tensile stresses due to bending. Experimental t ...

2021

Deformational behavior and damage mechanism of R-UHPFRC beam subjected to fatigue loading

Eugen Brühwiler, Bartlomiej Wojciech Sawicki, Antoine Bassil

The fatigue behavior of a reinforced UHPFRC (Ultra High Performance Fiber Reinforced Cementitious composite) T-shaped beam under four-point bending is investigated. The beam was subjected to a fatigue loading range equal to 49% of the static resistance and ...

2021

Fatigue examination of reinforced-concrete bridge slabs using acoustic emission and strain monitoring data

Imane Bayane

The examination of bridges under service loading is key for understanding their condition and thus for their sustainable and efficient use. The need to extend the service duration of existing bridges is increasing, and therefore, efficient tools for examin ...

EPFL2021

Fatigue of reinforced UHPFRC members and monitoring of fatigue action effects on bridges

Bartlomiej Wojciech Sawicki

The objective of this thesis is to develop knowledge and methods to prevent fatigue failure of bridges. The Fatigue Limit State is investigated from both the demand (S) and resistance (R) side. The S-part focuses on reduction of uncertainties through monit ...

EPFL2021

Multiaxial fatigue behavior and strengthening of riveted double-angle connections in steel bridges using prestressed CFRP rods

Hossein Heydarinouri

A large number of aging road and railway riveted metallic bridges suffer from fatigue problems. Stringer-to-floor-beam double-angle bridge connections are among the most fatigue-prone details due to the many cyclic distortion-induced stresses from axle loa ...

EPFL2021

Multiaxial fatigue analysis of high-strength steel welded joints using generalized local approaches

Martin Antonio René Garcia

The objective of this thesis is to improve methods for predicting the fatigue life, multiaxial or not, of mild- and more particularly high-strength steels using local approaches that have the capacity to be applicable to almost any cases, hence the term ge ...

EPFL2020

Experimental evaluation and modeling of fatigue of a 316L austenitic stainless steel in high-temperature water and air environments

Wen Chen

Austenitic stainless steels is used in many components of nuclear power plants, particularly in the pipes of cooling systems. Owing to power transients and to start-ups and shutdowns, these components are subjected to thermo-mechanical loadings (low-cycle ...

EPFL2020

Static and Fatigue Biaxial Flexural Behavior of Strain-Hardening UHPFRC Thin Slab Elements

Xiujiang Shen

Cast-in-place thin layers of Ultra-High Performance Fiber Reinforced Cementitious Composites (UHPFRC) on the specific zones of existing reinforced concrete (RC) bridge decks has been demonstrated to be a technically efficient and economic rehabilitation an ...

EPFL2020

3D laser shock peening - A new method for improving fatigue properties of selective laser melted parts

Christian Leinenbach, Manuel Ortega Varela De Seijas, Roland Logé, Nikola Kalentics

Although Selective Laser Melting (SLM) currently revolutionizes the way parts are being manufactured, certain process inherent limitations such as accumulation of residual stresses and increased porosity content can lead to a decrease in fatigue life of pr ...

ELSEVIER2020

Stress ratio effect on tension-tension fatigue behavior of angle-ply GFRP laminates

Thomas Keller, Anastasios Vassilopoulos

The effect of the stress ratio (R = sigma(min)/sigma(max)) on the fatigue behavior of (+/- 45)(2s) angle-ply glass/epoxy composite laminates was investigated by comparing their mechanical, thermal, and optical properties under the stress ratio of 0.5 with ...

2019

Multiaxial ultra low cycle fatigue in welded high strength steel structural components

Alain Nussbaumer, Albano António De Abreu E Presa De Castro E Sousa

Extreme events often subject regions of structural steel components to large inelastic strains. In conditions such as earthquakes, exceptional winds gusts or tides the loading scenario is cyclical, variable amplitude and frequently multiaxial in nature, an ...

2019

Load history effects in fibre-reinforced polymer composite materials

Abdolvahid Movahedirad

Today, it is widely accepted that fatigue is one of the most common failure mechanisms in structural components, and pure static failure is rarely observed. Engineering structures are subjected to complex mechanical fatigue loading histories, which cause d ...

EPFL2019

Two-dimensional crack growth in FRP laminates and sandwich panels

Aida Cameselle Molares

Fiber-reinforced polymer (FRP) composite materials are currently being selected for the design of lightweight and efficient structural members in a wide number of engineering applications. Sandwich panels with glass fiber-reinforced polymer (GFRP) face she ...

EPFL2019

Fatigue safety verification of a steel railway bridge using short term monitoring data

Eugen Brühwiler, Bartlomiej Wojciech Sawicki, Mariia Nesterova

The case study of the fatigue safety examination of the 120 years old steel riveted bridge carrying a single railway track on two main girders is presented. The overall assessment according to the Swiss Standard SIA 269 for existing structures indicated su ...

CRC PRESS-TAYLOR & FRANCIS GROUP2019

Modeling of fatigue behavior based on interaction between time- and cyclic-dependent mechanical properties

Thomas Keller, Anastasios Vassilopoulos

A general constitutive equation was established using the theory of viscoelasticity in order to consider the interaction of the time- and cyclic-dependent mechanical properties of laminated composites. This equation was solved for two specific loading patt ...

2019

Numerically-based method for fracture characterization of Mode I-dominated two-dimensional delamination in FRP laminates

Thomas Keller, Anastasios Vassilopoulos, Aida Cameselle Molares

A new numerically-based method suitable for determining the total strain energy release rate (SERA) involved in two-dimensional (2D) Mode I-dominated delamination under opening loads in FRP laminates is presented. The method is based on the mutual dependen ...

2019