@Article{AAMM-14-1,
author = {Yi, Wei and Rao, Qiuhua and Zhu, Wei and Shen, Qingqing and Zhuo, Li and Wenbo, Ma},
title = {Interacting Stress Intensity Factors of Multiple Elliptical-Holes and Cracks Under Far-Field and Arbitrary Surface Stresses},
journal = {Advances in Applied Mathematics and Mechanics},
year = {2022},
volume = {14},
number = {1},
pages = {125--154},
abstract = {<p style="text-align: justify;">Calculating interacting stress intensity factors (SIFs) of multiple elliptical-holes and cracks is very important for safety assessment, stop-hole optimization design and resource exploitation production in underground rock engineering, e.g., buried tunnels, deep mining, geothermal and shale oil/gas exploitation by hydraulic fracturing technology, where both geo-stresses and surface stresses are applied on buried tunnels, horizontal wells and natural cracks. However, current literatures are focused mainly on study of interacting SIFs of multiple elliptical-holes (or circular-holes) and cracks only under far-field stresses without consideration of arbitrary surface stresses. Recently, our group has proposed a new integral method to calculate interacting SIFs of multiple circular-holes and cracks subjected to far-filed and surface stresses. This new method will be developed to study the problem of multiple elliptical-hole and cracks subjected to both far-field and surface stresses. In this study, based on Cauchy integral theorem, the exact fundamental stress solutions of single elliptical-hole under arbitrarily concentrated surface normal and shear forces are derived to establish new integral equation formulations for calculating interacting SIFs of multiple elliptical-holes and cracks under both far-field and arbitrary surface stresses. The new method is proved to be valid by comparing our results of interacting SIFs with those obtained by Green&#39;s function method, displacement discontinuity method, singular integral equation method, pseudo-dislocations method and finite element method. Computational examples of one elliptical-hole and one crack in an infinite elastic body are given to analyze influence of loads and geometries on interacting SIFs. Research results show that when $\sigma_{x x}^{\infty} \geq \sigma_{y y}^{\infty}$, there appears a neutral crack orientation angle $\beta_0$ (without elliptical-hole&#39;s effect). Increasing $\sigma_{x x}^{\infty} / \sigma_{y y}^{\infty}$&nbsp; and $b/a$ (close to circular-hole) usually decreases $\beta_0$ of $K_I$ and benefits to the layout of stop-holes. The surface compressive stresses applied onto elliptical-hole $(n)$ and crack $(p)$ have significant influence on interacting SIFs but almost no on $\beta_0$. Increasing $n$ and $p$ usually results in increase of interacting SIFs and facilitates crack propagation and fracture networks. The elliptical-hole orientation angle $(\alpha)$ and holed-cracked distance $(t)$ have great influence on the interacting SIFs while have little effect on $\beta_0$. The present method is not only simple (without any singular parts), high-accurate (due to exact fundamental stress solutions) and wider applicable (under far-field stresses and arbitrarily distributed surface stress) than the common methods, but also has the potential for the anisotropic problem involving multiple holes and cracks.</p>},
issn = {2075-1354},
doi = {https://doi.org/10.4208/aamm.OA-2021-0057},
url = {https://global-sci.com/article/72894/interacting-stress-intensity-factors-of-multiple-elliptical-holes-and-cracks-under-far-field-and-arbitrary-surface-stresses}
}