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Портал Begell Электронная Бибилиотека e-Книги Журналы Справочники и Сборники статей Коллекции
International Journal for Multiscale Computational Engineering
Импакт фактор: 1.016 5-летний Импакт фактор: 1.194 SJR: 0.554 SNIP: 0.68 CiteScore™: 1.18

ISSN Печать: 1543-1649
ISSN Онлайн: 1940-4352

Выпуски:
Том 17, 2019 Том 16, 2018 Том 15, 2017 Том 14, 2016 Том 13, 2015 Том 12, 2014 Том 11, 2013 Том 10, 2012 Том 9, 2011 Том 8, 2010 Том 7, 2009 Том 6, 2008 Том 5, 2007 Том 4, 2006 Том 3, 2005 Том 2, 2004 Том 1, 2003

International Journal for Multiscale Computational Engineering

DOI: 10.1615/IntJMultCompEng.v5.i2.80
pages 153-165

Nonlocal Elastic-Damage Interface Mechanical Model

Guido Borino
Università di Palermo, Dipartimento di Ingegneria Strutturale e Geotecnica Viale delle Scienze, I-90128 Palermo, Italy
Boris Failla
Università di Palermo, Dipartimento di Ingegneria Strutturale e Geotecnica Viale delle Scienze, I-90128 Palermo, Italy
Francesco Parrinello
Università di Palermo, Dipartimento di Ingegneria Strutturale e Geotecnica Viale delle Scienze, I-90128 Palermo, Italy

Краткое описание

The paper presents a nonlocal extension of the elastic-damage interface mechanical model, which is able to describe the effects of the spatially extended microstructure on the decohesion (or fracture) process along a surface. The key feature of the proposed model is an integral constitutive relation between tractions and displacement jumps at the interface. The presence of an integral kernel brings in the model an internal length measure, which characterizes the transition from the microscale, dominated by heterogeneities and discontinuous media, to the mesoscale, characterized as an enhanced homogenized continuum with nonlocal features. The motivations and the fields of applications of the presented approach are rooted on the observation that, in many micromechanical circumstances, the potential process zone, where decohesion might develop, involves a spatial extended and organized microstructure, that produces complex elastic bridging spatial effects. The present model is a generalization of the classical (local) interface and should be adopted when the size of the microstructure, in the interface, is comparable to the size of the process zone. Typically, spatial constitutive interactions can be well modeled by means of integral (nonlocal) relations. In nonlocal constitutive equations, the stress at a point is related to the strain field at the neighboring points, by means of an integral weighting relation. The nonlocal interface constitutive relations are developed following a thermodynamically consistent approach. The damage development along the interface is driven by a nonlocal damage activation function, where the damage driving force is related to a nonlocal strain measure. Namely, a spatial average energy release rate is responsible for the local decohesion development. The model has been implemented in a finite element code, and some numerical applications of microfracture are examined.