Publications associées à Optimization of multi-directional fiber architecture for resistance and ductility of bolted FRP profile joints

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

Quench Detection and Temperature Measurement With Fiber Optic Sensors

Davide Uglietti, Kamil Sedlák, Christoph Müller

For the EU DEMO conductor testing, a temperature sensor based on Fiber Bragg Grating (FBG) optical fiber is studied at the EPFL Swiss Plasma Center. The SULTAN test facility has been upgraded to use fiber optic sensor for temperature monitoring and quench ...

IEEE Institute of Electrical and Electronics Engineers2024

Capsizing due to friction-induced twist in the failure of stopper knots

Pedro Miguel Nunes Pereira de Almeida Reis, Paul Johanns

We investigate the failure mechanism of stopper knots, with a particular focus on the figure -8 knot as a representative example. Stopper knots are widely used in climbing, sailing, racket stringing, and sewing to maintain tension in ropes, strings, or thr ...

Elsevier2024

Model uncertainties in action effects and load bearing capacity calculation in statically indeterminate reinforced concrete structures

Alain Nussbaumer, Aurelio Muttoni, Xhemsi Malja

For the dimensioning and assessment of structures, it is common practice to compare action effects with sectional resistances. Extensive studies have been performed to quantify the model uncertainty on the resistance side. However, for statically indetermi ...

Ernst & Sohn2024

Effect of fiber architecture on tension-tension fatigue behavior of bolted basalt composite joints

Thomas Keller, Lulu Liu, Xin Wang

The effect of fiber architecture, i.e., unidirectional (UD) vs. multi-directional (MD), on the tension-tension fa-tigue behavior of bolted double-lap basalt composite joints was experimentally investigated. The fatigue load-life (F -N) curves of MD and UD ...

ELSEVIER SCI LTD2023

A Discussion on the Reliability of prEN1992-1-1:2021 Shear Strength Provisions for Fibre Reinforced Concrete Members Without Shear Reinforcement

Miguel Fernández Ruiz

The Eurocode 2 for the design of concrete structures (EN1992-1-1:2004) is undergoing a revision that will lead to the publication of the second generation of this code to be used across all CEN member countries. Therefore, the impact of the code will reach ...

SPRINGER INTERNATIONAL PUBLISHING AG2023

Humidity-insensitive optical fibers for distributed sensing applications

Luc Thévenaz, Tiago Filipe Pimentel Das Neves

Humidity is a critical environmental factor in various applications, and its temperature dependence must be considered when developing thermo-hygrometer fiber sensors. The optical fibers that constitute the sensor must have a temperature reference, which s ...

2023

Space-time wave packets with reduced divergence and tunable group velocity generated in free space after multi-mode fiber propagation

Tobias Kippenberg, Hao Song, Maxim Karpov, Xinzhou Su

Previously, space-time wave packets (STWPs) have been gen-erated in free space with reduced diffraction and a tunable group velocity by combining multiple frequency comb lines each carrying a single Bessel mode with a unique wave num-ber. It might be poten ...

Optica Publishing Group2023

Fatigue behavior and life prediction of wind turbine blade composite materials

Anastasios Vassilopoulos

Fatigue life prediction of wind turbine rotor blades is a very challenging task, as their failure is led by different failure types that act synergistically. Inherent defects like wrinkles, fiber misalignments, and voids that can be introduced during fabri ...

Woodhead Publishing (Elsevier)2023

Study on the possibility of Φ-OTDR sensing in hollow-core fibres

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Yuting Yang

The backscattering process in hollow core fibres shows a large similarity with Rayleigh scattering, offering the potential to be exploited for distributed sensing. A classical Φ-OTDR implementation is used to observe the backscattering signal from the surf ...

SPIE2023

Reliability analysis and partial safety format calibration considering the characteristics of the resistance of reinforced concrete structures

Qianhui Yu

Every engineering calculation is an approximation of reality, with inevitable uncertainties involved. This fact implies that a reliability verification accounting for the uncertainties is a necessary step in the design and assessment of structures. Nowaday ...

EPFL2023

Process development of pre-impregnated hybrid thin-ply composites

Alexios Argyropoulos

Thin-ply composites, obtained with recently developed fiber spreading techniques, rapidly gained industrial interest because they offer a large composite design freedom, and lead to a composite tensile strength that is close to that of the individual fiber ...

EPFL2023

Equivalent Frame Models for FRP-Strengthened Masonry Buildings

Fibre-reinforced polymers (FRP) strengthening can be applied to decrease the seismic vulnerability of existing masonry buildings, both with regard to in-plane and out-of-plane failure mechanisms. Experimentally, the impact of strengthening solutions has be ...

Proceedings of the 2nd Croatian Conference on Earthquake Eng2023

A photonic integrated circuit-based erbium-doped amplifier

Rui Ning Wang, Tobias Kippenberg, Junqiu Liu, Anton Lukashchuk, Jijun He, Xinru Ji, Yang Liu, Zheru Qiu

Erbium-doped fiber amplifiers revolutionized long-haul optical communications and laser technology. Erbium ions could provide a basis for efficient optical amplification in photonic integrated circuits but their use remains impractical as a result of insuf ...

American Association for the Advancement of Science2022

SBS-based fiber sensors

Luc Thévenaz

The spectra of Brillouin scattering processes in optical fibers are affected by temperature, axial strain, and other quantities of interest. This dependence forms the basis for optical Brillouin scattering based optical fiber sensors. Since the first propo ...

Elsevier2022

Functionalization of polymer optical fibers for medical application

Jialuo Luo

The increasing challenges caused by the growing and aging population and the fast pace of life are calling for a change of our current medical care system towards being rapid, easy, and on-demand self-care. Empowerment with the self-caring components such ...

EPFL2022

Thermophysical and thermomechanical properties of basalt-phenolic FRP rebars under high temperature

Thomas Keller, Hongwei Zhu, Ting Li, Jiahui Shen

An experimental investigation was conducted on the thermophysical and thermomechanical properties of phenolic-basalt fiber-reinforced polymer (P-BFRP) rebars subjected to high temperature. As a comparison, vinylBFRP (V-BFRP) and epoxy-BFRP (E-BFRP) rebars ...

ELSEVIER SCI LTD2022

Shear Response of Wet Weak Carbonate Rock/Grout Interfaces Under Cyclic Loading

Eleni Stavropoulou

The development and construction of offshore wind farms requires the correct estimation of the friction that can be mobilised at the rock/grout interface. In conventional studies, the shear behaviour of a joint is usually investigated with laboratory tests ...

2021

Ultimate Feature Sizes in Thermally Drawn Fibers: from Fundamental Analysis to Novel Functional Fibers

Inès Richard

The fiber thermal drawing process has emerged as a simple and scalable technique for the fabrication of multifunctional and flexible electronics. The integration of materials with various physical and functional properties in well-defined architectures ope ...

EPFL2021

Wavelength-Division Multiplexed Optical Cryptocurrency

Maxim Karpov

We propose an optical proof-of-work scheme that feeds data encoded into wavelength-division multiplexed modes through a programmable photonic network. We verify robustness by modeling network dispersion, allowing for energy-efficient optical alternatives t ...

IEEE2021