Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens

Mixed mode crack propagation analysis has been more accessible with the development of new numerical tools, allowing to evaluate the influence of non-mode I loadings in the crack path and in the growth rate. The aim of this work is to analyse the propagation of pre-existing cracks under pure mode I,...

Full description

Saved in:
Bibliographic Details
Main Authors: Sérgio Alexandre Gonçalves Pereira, Sérgio M.O. Tavares, Paulo M.S.T. de Castro
Format: Article
Language:English
Published: Gruppo Italiano Frattura 2019-06-01
Series:Fracture and Structural Integrity
Subjects:
Online Access:https://www.fracturae.com/index.php/fis/article/view/2316
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1841562822564118528
author Sérgio Alexandre Gonçalves Pereira
Sérgio M.O. Tavares
Paulo M.S.T. de Castro
author_facet Sérgio Alexandre Gonçalves Pereira
Sérgio M.O. Tavares
Paulo M.S.T. de Castro
author_sort Sérgio Alexandre Gonçalves Pereira
collection DOAJ
description Mixed mode crack propagation analysis has been more accessible with the development of new numerical tools, allowing to evaluate the influence of non-mode I loadings in the crack path and in the growth rate. The aim of this work is to analyse the propagation of pre-existing cracks under pure mode I, pure mode II and unstable mixed mode I-II loading conditions. Numerical simulations with two-dimensional models created in Abaqus software were performed, and the results obtained were compared with the analytical and experimental results. To determine T-stress and stress intensity factors, the conventional finite element method was used, post-processed with the modified virtual crack closure technique (mVCCT) and / or the J-integral. The extended finite element method (XFEM) is also used to predict the crack trajectory under different loading conditions. The experimental procedures were performed in three and four-point bending tests on single edge notch specimens of PMMA, in which a natural pre-crack was created by small impacts with a hammer on a blade located over the pre-existing machined notch. The four-point bending test was performed with an asymmetrical configuration. Varying the locations of supports and loading points with respect to the crack plane, this configuration allows to create pure mode II and mixed-mode I-II situations. The three-point bending test was performed in the conventional manner, with only the distance from the load line to the crack plane being varied.
format Article
id doaj-art-0c0a2ab8bd8245098c3b8a00005a1de3
institution Kabale University
issn 1971-8993
language English
publishDate 2019-06-01
publisher Gruppo Italiano Frattura
record_format Article
series Fracture and Structural Integrity
spelling doaj-art-0c0a2ab8bd8245098c3b8a00005a1de32025-01-03T00:40:22ZengGruppo Italiano FratturaFracture and Structural Integrity1971-89932019-06-011349Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimensSérgio Alexandre Gonçalves Pereira0Sérgio M.O. TavaresPaulo M.S.T. de CastroFEUPMixed mode crack propagation analysis has been more accessible with the development of new numerical tools, allowing to evaluate the influence of non-mode I loadings in the crack path and in the growth rate. The aim of this work is to analyse the propagation of pre-existing cracks under pure mode I, pure mode II and unstable mixed mode I-II loading conditions. Numerical simulations with two-dimensional models created in Abaqus software were performed, and the results obtained were compared with the analytical and experimental results. To determine T-stress and stress intensity factors, the conventional finite element method was used, post-processed with the modified virtual crack closure technique (mVCCT) and / or the J-integral. The extended finite element method (XFEM) is also used to predict the crack trajectory under different loading conditions. The experimental procedures were performed in three and four-point bending tests on single edge notch specimens of PMMA, in which a natural pre-crack was created by small impacts with a hammer on a blade located over the pre-existing machined notch. The four-point bending test was performed with an asymmetrical configuration. Varying the locations of supports and loading points with respect to the crack plane, this configuration allows to create pure mode II and mixed-mode I-II situations. The three-point bending test was performed in the conventional manner, with only the distance from the load line to the crack plane being varied.https://www.fracturae.com/index.php/fis/article/view/2316LEFMMixed mode I-IIStress intensity factorExtended finite element methodCrack path
spellingShingle Sérgio Alexandre Gonçalves Pereira
Sérgio M.O. Tavares
Paulo M.S.T. de Castro
Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens
Fracture and Structural Integrity
LEFM
Mixed mode I-II
Stress intensity factor
Extended finite element method
Crack path
title Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens
title_full Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens
title_fullStr Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens
title_full_unstemmed Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens
title_short Mixed mode fracture: numerical evaluation and experimental validation using PMMA specimens
title_sort mixed mode fracture numerical evaluation and experimental validation using pmma specimens
topic LEFM
Mixed mode I-II
Stress intensity factor
Extended finite element method
Crack path
url https://www.fracturae.com/index.php/fis/article/view/2316
work_keys_str_mv AT sergioalexandregoncalvespereira mixedmodefracturenumericalevaluationandexperimentalvalidationusingpmmaspecimens
AT sergiomotavares mixedmodefracturenumericalevaluationandexperimentalvalidationusingpmmaspecimens
AT paulomstdecastro mixedmodefracturenumericalevaluationandexperimentalvalidationusingpmmaspecimens