Iranian Journal of Mechanical Engineering Transactions of ISME

Iranian Journal of Mechanical Engineering Transactions of ISME

Calculation of asymptotic stress field, Stress intensity factors and higher order terms in key-hole notches

Authors
Majid Reza Ayatollahi 1
Bahador Bahrami 2
A.M. Mirzaie 2
1 Department of Mechanical Engineering, Iran Science and Technology
2 Iran University of Science and Technology
Abstract
In the present study, the asymptotic stress distribution related to the mode I loading has been calculated by using the complex potential functions method for the key-hole notch. The new solution is an extension to the previous study of Zappalorto and Lazzarin [1] and has been developed to derive the components of stress field in the series expansion. Moreover, the displacement fields around the keyhole notch have been derived in both Cartesian and polar coordinate systems. Then, the over-deterministic method is utilized to calculate the coefficients of the series. According to the over-deterministic method the asymptotic stress or displacement field will be fitted to a large number of data points and the coefficients of the series will be derived based on the least square sense. Finally, to evaluate the derived coefficients, the truncated stress series have been compared with its relevant finite element values. The results show that considering the singular terms alone will generate large amounts of errors in calculations.
Keywords
Higher order terms
key-hole notch
mode I loading
over-deterministic method

Subjects

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Iranian Journal of Mechanical Engineering Transactions of ISME
Volume 21, Issue 3 - Serial Number 56
System Dynamics and Solid Mechanics
Autumn 2019
Pages 225-243

  • Receive Date 11 July 2018
  • Revise Date 31 July 2018
  • Accept Date 19 January 2020