Publication detail

Analysis of accuracy of Williams series approximation of stress field in cracked body – influence of area of interest around crack-tip on multi-parameter regression performance

SOBEK, J. FRANTÍK, P. VESELÝ, V.

Original Title

Analysis of accuracy of Williams series approximation of stress field in cracked body – influence of area of interest around crack-tip on multi-parameter regression performance

Type

journal article in Web of Science

Language

English

Original Abstract

A study on the accuracy of an approximation of the stress field in a cracked body is presented. Crack-tip stress tensor is expressed using the linear elastic fracture mechanics (LEFM) theory in this work, more precisely via its multi-parameter formulation, i.e. by Williams power series (WPS). Determination of coefficients of terms of this series is performed using a least squares-based regression technique known as over-deterministic method (ODM) for which results from finite element (FE) method computation are usually taken as inputs. Main attention is paid to a detailed analysis of a suitable selection of FE nodes whose results serve as the inputs to the employed method. Two different ways of FE nodal selection are compared – nodes selected from the crack tip vicinity lying at a ring of a certain radius versus nodes selected more or less uniformly from a specified part of the test specimen body. Comparison of these approaches is made with the help of procedures developed by the authors which enable both the determination of the coefficients of terms of the analytical WPS approximation of the stress field based on the FE results and the backward reconstruction of the field (again using WPS) from those determined terms’ coefficients/functions. The wedge-splitting test (WST) specimen with a crack is taken as example for the study

Keywords

Multi-parameter fracture mechanics, Williams power series, Crack-tip fields, Over-deterministic method, Higher order terms

Authors

SOBEK, J.; FRANTÍK, P.; VESELÝ, V.

Released

1. 1. 2017

Publisher

Gruppo Italiano Frattura

ISBN

1971-8993

Periodical

Frattura ed Integrita Strutturale

Year of study

11

Number

39

State

Republic of Italy

Pages from

129

Pages to

142

Pages count

14

URL

http://www.gruppofrattura.it/pdf/rivista/numero39/numero_39_art_14.pdf

Full text in the Digital Library

http://hdl.handle.net/11012/180652

BibTex

@article{BUT131289,
  author="Jakub {Sobek} and Petr {Frantík} and Václav {Veselý}",
  title="Analysis of accuracy of Williams series approximation of stress field in cracked body – influence of area of interest around crack-tip on multi-parameter regression performance",
  journal="Frattura ed Integrita Strutturale",
  year="2017",
  volume="11",
  number="39",
  pages="129--142",
  doi="10.3221/IGF-ESIS.39.14",
  issn="1971-8993",
  url="http://www.gruppofrattura.it/pdf/rivista/numero39/numero_39_art_14.pdf"
}