Incremental displacement collocation method for the determination of fracture properties of quasi-brittle materials

This paper deals with fracture properties of microlevel components of hydrated cementpaste. Determination of fracture energy and fracture toughness for quasi-brittle materials hasbecome a challenge for many years on both macro- and micro-scales. Limited number of quantitative data can be found in the literature for the micro-scale. This work uses energetic approach and decomposition of work of indentation into plastic and other parts. Based on simplified assumptions fracture energy and fracture toughness are calculated for individual microstructural phases of cement paste with the aid of nanoindentation, statistical deconvolution and fracture mechanics.

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Determination of uniaxial tensile strength of brittle materials using tubular samples

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/833/1/012016 ◽

2021 ◽

Vol 833 (1) ◽

pp. 012016

Author(s):

D J Guerrero-Miguel ◽

M I Alvarez-Fernández ◽

M B Prendes-Gero ◽

C González-Nicieza

Keyword(s):

Tensile Strength ◽

Brittle Materials ◽

Uniaxial Tensile ◽

Uniaxial Tensile Strength

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Convergence Study on Application of the Over-Deterministic Method for Determination of Near-Tip Fields in a Cracked Plate Loaded in Mixed-Mode

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.249-250.76 ◽

2012 ◽

Vol 249-250 ◽

pp. 76-81 ◽

Cited By ~ 6

Author(s):

Lucie Šestáková ◽

Václav Veselý

Keyword(s):

Mixed Mode ◽

Brittle Materials ◽

Higher Order ◽

Displacement Fields ◽

Deterministic Method ◽

Crack Behavior ◽

Stress And Displacement Fields ◽

Higher Order Terms ◽

Convergence Study

Multi-parameter description of crack behavior in quasi-brittle materials offers still enough space for investigations. Several studies have been carried out by the authors in this field [1-3]. One part of the publications by the authors (this work included) contain analyses of the accuracy, convergence and/or tuning of the over-deterministic method that enables determination of the coefficients of the higher-order terms in Williams expansion approximating the stress and displacement fields in a cracked body without any complicated FE formulations. These intermediate studies should bring together a list of recommendations how to use the ODM as effectively as possible and obtain reliable enough values of coefficients of the higher-order terms. Thus, the stress/displacement field can be determined precisely even in a larger distance from the crack tip, which is crucial for assessment of the fracture occurring in quasi-brittle materials.

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A novel local radial basis function collocation method for multi-dimensional piezoelectric problems

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x211057207 ◽

2021 ◽

pp. 1045389X2110572

Author(s):

Amir Noorizadegan ◽

Der Liang Young ◽

Chuin-Shan Chen

Keyword(s):

Radial Basis Function ◽

Collocation Method ◽

Basis Function ◽

Shape Parameter ◽

Piezoelectric Medium ◽

The Finite Element Method ◽

Mechanical Field ◽

Radial Basis ◽

2D And 3D

The local radial basis function collocation method (LRBFCM), a strong-form formulation of the meshless numerical method, is proposed for solving piezoelectric medium problems. The proposed numerical algorithm is based on the local Kansa method using variable shape parameter. We introduce a novel technique for the determination of shape parameter in the LRBFCM, which leads to greater accuracy, and simplicity. The implemented algorithm is first verified with a 2D Poisson equation. Then, we employed LRBFCM in a numerical simulation for 2D and 3D piezoelectric problems involving mutual coupling of the electric field and elastodynamic equations for mechanical field. The presented meshless method is verified using corresponding results obtained from the finite element method and moving least squares meshless local Petrov–Galerkin method. In particular, the 2D piezoelectric problem is verified with an exact solution.

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Numerical Modeling of Brittle Materials by Damage Plasticity Model: Determination of Parameters with Consideration of Size Effects Due to Tensile Cracking and Compressive Crushing

Lecture Notes in Civil Engineering - Geotechnics for Sustainable Infrastructure Development ◽

10.1007/978-981-15-2184-3_138 ◽

2019 ◽

pp. 1065-1071

Author(s):

Duc An Ho ◽

Marion Bost ◽

Jean-Pierre Rajot

Keyword(s):

Numerical Modeling ◽

Size Effects ◽

Brittle Materials ◽

Plasticity Model ◽

Model Determination ◽

Determination Of Parameters

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Size Effect in Fracture Toughness Determination of Brittle Materials

Advances in Science and Technology - 11th International Ceramics Congress ◽

10.4028/3-908158-01-x.101 ◽

2006 ◽

pp. 101-106

Author(s):

Zdeněk Chlup ◽

Ivo Dlouhy

Keyword(s):

Fracture Toughness ◽

Size Effect ◽

Brittle Materials

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First-Principles Determination Of The Effects Of Boron And Sulfur On The Ideal Cleavage Fracture In Ni3Al

MRS Proceedings ◽

10.1557/proc-409-183 ◽

1995 ◽

Vol 409 ◽

Author(s):

Sheng N. Sun ◽

Nicholas Kioussis ◽

Mikael Ciftan ◽

A. Gonis

Keyword(s):

Cleavage Fracture ◽

First Principles ◽

Cleavage Plane ◽

Full Potential ◽

Fracture Properties ◽

Electronic Mechanism ◽

Strain Relationship ◽

First Time ◽

The Ideal

AbstractThe effects of boron and sulfur impurities on the ideal cleavage fracture properties of Ni3Al under tensile stress are investigated for the first time using the full-potential linearmuffin- tin-orbital (FLMTO) total-energy method, with a repeated slab arrangement of atoms simulating an isolated cleavage plane. Results for the stress-strain relationship, ideal cleavage energies, ideal yield stress and strains with and without impurities are presented, and the electronic mechanism underlying the contrasting effects of boron and sulfur impurities on the ideal cleavage of Ni3Al is elucidated.

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