Publications related to Active repair of self-healing polymers with shape memory alloy wires

Two-dimensional quasi-static delamination in composite laminates under Mode-I and Mode-II conditions

Fiber-polymer composites consist of a polymer matrix and reinforcing fibers made of various materials. These composites exhibit exceptional properties, such as a high strength-to-weight ratio and excellent corrosion resistance, which has led to their incre ...

EPFL2024

Numerical investigation of two-dimensional Mode-II delamination in composite laminates

Thomas Keller, Anastasios Vassilopoulos, Congzhe Wang

Existing standards for delamination tests on composite materials typically employ one-dimensional (1D) beam specimens. However, such specimens may not represent real delamination scenarios in composite structures, where cracks tend to propagate in two dime ...

Elsevier Sci Ltd2024

An adaptive phase field approach to 3D internal crack growth in rocks

Tao Xu, Michael Heap, Alexandra Roma Larisa Kushnir

Modeling the 3D internal crack under compression entails complex fracture mechanics (mode I-II-III fracture), resulting in substantial computational costs and challenges in characterizing fracture morphology characterization for Phase Field Method (PFM) si ...

2024

Mode I fracture of thick adhesively bonded GFRP composite joints for wind turbine rotor blades

Véronique Michaud, Anastasios Vassilopoulos, Jialiang Fan

This article investigates the effects of voids, joint geometry, and test conditions on the quasi-static Mode I fracture performance of thick adhesive Double Cantilever Beam (DCB) joints such as those prevailing in wind industry and shipbuilding. The specim ...

2024

Estimation of the bar stress based on crack width measurements in reinforced concrete structures

Aurelio Muttoni, Enrique Corres Sojo

Estimating the stress of reinforcing bars and its variations in service conditions can be useful to determine the reserve capacity of structures or to assess the risk of fatigue in the reinforcement. This paper investigates the use crack width measurements ...

Ernst & Sohn2024

The General Crack Component Model for reversed cyclic shear

David Michael Volpe Ruggiero

A growing body of research has shown that reversed cyclic shear loading of reinforced concrete (RC) causes effects that are not accounted for in monotonic behavioral models. Notable among these effects are a reduction in shear strength and significant plas ...

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

CRACK SHIELDING MECHANISMS OF INTERLAYERED EPOXY MATERIALS UNDER QUASI-STATIC AND FATIGUE LOADING

Anastasios Vassilopoulos, Dharun Vadugappatty Srinivasan

This research explores the capability of PEI and PVDF thermoplastic interlayers to arrest cracks in epoxy materials modified with short-glass fibers and core-shell rubber particles. It also investigates the effect of interlayer position, the number of inte ...

Queen's University Belfast2023

Laser powder bed fusion of Fe-based shape memory alloys for novel structural metamaterials and "smart" structures

Irene Ferretto

Laser powder bed fusion (LPBF) is a powder-based additive manufacturing (AM) technique, which shows great potential in the production of complex-shaped parts with unprecedented design freedom. In addition, it allows for an active manipulation of the micros ...

EPFL2023

Three-dimensional hydraulic fracture propagation in homogeneous and heterogeneous media

Carlo Peruzzo

Hydraulic fractures are tensile fractures that occur in solid materials due to the natural intrusion or anthropogenic injection of a viscous fluid into a fracture channel. The deliberate creation of hydraulic fractures is part of an industrial technology h ...

EPFL2023

Using video detection of snow surface movements to estimate weak layer crack propagation speeds

Bertil Trottet, Johan Alexandre Philippe Gaume, Alec van Herwijnen

Dry-snow slab avalanches release due to crack propagation in a weak snow layer under a cohesive snow slab. Crack propagation speeds can provide insights into the potential size of avalanches and inform fracture and avalanche release models. Despite their i ...

CAMBRIDGE UNIV PRESS2023

Multi-scale characterization and modeling of notched strength and translaminar fracture in hybrid thin-ply composites based on different carbon fiber grades

Guillaume Clément Broggi

Owing to their high specific stiffness and strength, Carbon Fiber Reinforced Composites (CFRP) are ideal candidates for the development of lightweight high-performance structures. Within this family, thin-ply composites allow for wider design freedom and p ...

EPFL2023

Mode I and Mode II fracture behavior in pultruded glass fiber-polymer - Experimental and numerical investigation

Thomas Keller

Many recent works have shown that the capacity of pultruded glass fiber-polymer structural members is governed by interlaminar failure. However, there is still a lack of information regarding the fracture properties associated and the best techniques to be ...

Elsevier Sci Ltd2023

Novel multi-crack damage approach for pultruded fiber-polymer web-flange junctions

Thomas Keller

This paper aims to propose a novel approach to assess the multi-crack behavior of layered fiber-polymer composites. The Compliance and R-curves generated from this novel approach were useful to understand the multiple delamination process, enabling to eval ...

Elsevier Sci Ltd2023

Propagation of planar three-dimensional buoyant hydraulic fractures

Andreas Möri

Hydraulic fractures are driven by an internal fluid pressure exceeding the minimum compressive stress, propagating in a direction perpendicular to the latter. This class of tensile fractures has gained interest over the last fifty years due to the developm ...

EPFL2023

Nucleation, propagation, and scale dependence of laboratory frictional ruptures; implications for earthquake mechanics

Federica Paglialunga

Earthquakes are natural phenomena that cause ground shaking and damage to people and infrastructures. Despite significant progress achieved in understanding how earthquakes start, propagate, and arrest, many aspects of their physics and mechanics remain no ...

EPFL2023

Room-temperature strength of the interfacial bond between silica inclusions and iron

Andreas Mortensen, Alejandra Inés Slagter, David Hernandez Escobar, Sergio Perosanz Amarillo

The strength of the interface between iron (Fe) and individual spherical silica (SiO2) inclusions of 5 +/- 1 mu m diameter is measured by means of in-situ micro-cantilever bending tests conducted under displacement control within a scanning electron micros ...

Pergamon-Elsevier Science Ltd2023

Understanding the mechanisms of adhesive wear for heterogeneous materials through atomistic simulations

Jean-François Molinari, Sacha Zenon Wattel, Antonio Joaquin Garcia Suarez

When two rough surfaces slide against each other, two main behaviors can be observed at the asperity level: A ductile behavior where the asperities tend to smooth out or a brittle behavior where the asperities detach and form debris. Recently, a critical l ...

2022

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

Determining crack kinematics from imaged crack patterns

Katrin Beyer, Amir Rezaie, Bryan German Pantoja Rosero, Ketson Roberto Maximiano Dos Santos

Determining the relationship between the cause of damage and the subsequent structural behavior of infrastructure systems requires an accurate characterization of the propagation of cracks, which represents the evolution of the damage state. When no inform ...

2022