Publications related to Toughness

Three-dimensional buoyant hydraulic fractures: finite volume release

Brice Tanguy Alphonse Lecampion, Andreas Möri

In impermeable media, a hydraulic fracture can continue to expand even without additional fluid injection if its volume exceeds the limiting volume of a hydrostatically loaded radial fracture. This limit depends on the mechanical properties of the surround ...

Cambridge University Press2023

Arrest Mechanisms of Buoyant Hydraulic Fractures

Brice Tanguy Alphonse Lecampion, Andreas Möri, Carlo Peruzzo, Dmitriy Garagash

Hydraulic fracturing (HF) treatments can form widespread fractures. Understanding their containment at depth is critical, given the positive buoyancy contrast between the fracturing fluid and the surrounding rock, promoting upward growth. We study arrest m ...

American Rock Mechanics Association (ARMA), OnePetro2023

Elongated hydraulic fracture emerging from layers of alternating fracture toughness

Brice Tanguy Alphonse Lecampion, Carlo Peruzzo

Whether used to enhance the hydrocarbon production from low permeability rocks or to measure the minimum in-situ principal stress in rock formations, height growth of a hydraulic fracture above the formation of interest is a key metric for the design of su ...

2023

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

Deformation and Fracture of Tough Microstructured Hydrogels

Michael David Kessler

Many natural materials are structured on different length scales. This structuring often leads to an intricate interplay between soft and stiff components, which significantly improves the fracture toughness of these materials. A class of soft material tha ...

EPFL2022

Manufacturing and toughening effects on the material properties of wind turbine blade adhesives

Anastasios Vassilopoulos, Dharun Vadugappatty Srinivasan

Hybrid adhesives can be developed using commercially available adhesive materials and customized to the required loading conditions. In this paper, SPABONDTM 820HTA (non-toughened) and SPABONDTM 840HTA (toughened) adhesives are hybridized by two strategies ...

2022

Improving the Accuracy of Fracture Toughness Measurement in Burst Experiments

Guanyi Lu, Yixuan Zhang

Experimental studies suggest that the fracture toughness of rocks increases with the confining pressure. Among many methods to quantify this dependency, a so-called burst experiment (Abou-Sayed, 1978) may be the most widely applied in practice. Its thick w ...

SPRINGER WIEN2022

Reinforcing hydrogels with in situ formed amorphous CaCO3

Esther Amstad, Matteo Hirsch, Ran Zhao, Tianyu Yuan, Huachuan Du, Michael David Kessler

Hydrogels are often employed for tissue engineering and moistening applications. However, they are rarely used for load-bearing purposes because of their limited stiffness and the stiffness-toughness compromise inherent to them. By contrast, nature uses hy ...

ROYAL SOC CHEMISTRY2022

Arrest of a radial hydraulic fracture upon shut-in of the injection

Brice Tanguy Alphonse Lecampion, Andreas Möri

We investigate the propagation and arrest of a radial hydraulic fracture upon the end of the injection. Depending on the regime of propagation at the time of shut-in of the injection, excess elastic energy may be stored in the surrounding medium. Once the ...

2021

Atomic scale investigations of fracture in metal alloys

Eleanor Yi Kei Mak

The demand for metal alloys with superior structural performance in industrial applications continues to increase, as does the need for more-energy efficient materials and methods. Many materials that are otherwise attractive for structural applications ar ...

EPFL2021

Effect of water on sandstone's fracture toughness and frictional parameters: Brittle strength constraints

Marie Estelle Solange Violay, Corentin Jean-Marie Rémi Noël

Water presence causes a dramatic reduction of sandstone strength. Under compressive stress conditions, the strength of a rock sample is controlled by frictional parameters and the fracture toughness of the material. Here, we report fracture toughness, fric ...

2021

Hybrid hydrogels for load-bearing implants

Céline Samira Wyss

Load-bearing tissues such as articular cartilage or meniscus are not infallible. They might fail due to trauma, over-solicitations, or diseases, which could subsequently alter the mobility of the patient. Repairing these damaged tissues in a minimally inva ...

EPFL2021

Deciphering the interactions between single arm dislocation sources and coherent twin boundary in nickel bi-crystal

Helena Van Swygenhoven

The introduction of a well-controlled population of coherent twin boundaries (CTBs) is an attractive route to improve the strength ductility product in face centered cubic (FCC) metals. However, the elementary mechanisms controlling the interaction between ...

Nature Research2021

A New Evaluation Criterion for Optimizing the Mechanical Properties of Toughened Polypropylene/Silica Nanocomposites

Hossein Pourrahmani

This study aims to experiment with the mechanical properties of polypropylene (PP)/thermoplastic elastomer/nano-silica/compatibilizer nanocomposite using the melt mixing method. The addition of polyolefin elastomers has proved to be an approachable solutio ...

SPRINGER2020

Intrinsic fracture behavior of Mg-Y alloys

William Curtin, Eleanor Yi Kei Mak

Pure magnesium (Mg) is an attractive metal for structural applications due to its low density, but also has low ductility and low fracture toughness. Dilute alloying of Mg with rare earth elements in small amounts improves the ductility, but the effects of ...

2020

Experiments and numerical modelling on angle-ply laminates under remote mode II loading

John Botsis, Georgios Pappas, Charlie Joseph Simon Blondeau

Delamination is a very frequent damage mechanism that affects the integrity of laminated composites. In this study, the effect of ply orientation on crack growth resistance was analyzed for three different anti-symmetric interfaces (+/- 30 degrees, +/- 45 ...

ELSEVIER SCI LTD2020

Measurement and prediction of the transformation strain that controls ductility and toughness in advanced steels

William Curtin, Helena Van Swygenhoven, Francesco Maresca, Efthymios Polatidis

New-generation multi-phase martensitic steels derive their high strength from the body-centered cubic (BCC) phase and high toughness from transformation of the metastable face-centered cubic (FCC) austenite that transforms into martensite upon loading. In ...

PERGAMON-ELSEVIER SCIENCE LTD2020

A new data set of granitic rock strength values from Yosemite Valley, California: applications to rock fall assessment

To explore connections between rock strength and rock falls, we undertook a comprehensive rock mechanics testing program for six granitic rock types in Yosemite Valley (California, USA) where rock falls are a common geomorphic and sometimes hazardous proce ...

2020

Mixed-mode fracture response of anti-symmetric laminates: Experiments and modelling

John Botsis

Multidirectional laminates are very often used in advanced structures. However, the existing data in the literature regarding their fracture response is not conclusive. In this work, the fracture response of a +45 degrees// -45 degrees interface is investi ...

ELSEVIER SCI LTD2020

Propagation of a fluid-driven fracture with fracture length dependent apparent toughness

Brice Tanguy Alphonse Lecampion, Dong Liu

We investigate the growth of a hydraulic fracture assuming a power-law dependence of material toughness with fracture length for plane strain and radial geometries. Such a toughness fracture length dependence models in a simple manner a toughening mechanis ...

2019