Comments on the article: “Modified Williams’ crack tip solution including crack face pressure”

Abstract

Recently Chao et al. published a paper named “Modified Williams’ crack tip solution including crack face pressure” . In this article they first address the classical Williams’ series expansion for crack tip stress fields , which assumes no load pressure applied on the crack face. Subsequently, they repeat the same procedure but applying with an opposing boundary condition to solve the stress field written with the Airy stress function in bi-harmonic form. This approach enables them to successfully derive an expression for the T-stress when a pressure is applied on the crack face, considering only the first and second terms of the Williams’s series expansion.However, the solution they present (equation number 14 of the referenced paper) for the homogeneous boundary conditions (absence of applied pressure), contains an error when the subscript “i” is odd and greater than 2. In this correspondence, we present the correct solution, verified with the well-known expression of the Williams expansion series for mode I.