An easy and engineering stability criterion of general singular stress concentrators

• Published in: Theoretical and applied fracture mechanics 2019-12, Vol.104, p.102341, Article 102341
• Main Authors: Klusák, J., Krepl, O., Profant, T.
• Format: Article
• Language: English
• Subjects: Concentrators; Controlling quantity; Crack initiation; Crack propagation; Engineering; Fracture mechanics; General singular stress concentrator; Materials handling; Notches; Stability criteria; Stability criterion; Stress propagation
• ISSN: 0167-8442; 1872-7638
• DOI: 10.1016/j.tafmec.2019.102341

•An engineering failure criterion of general singular stress concentrators was assessed.•The criterion uses numerical results and easy formula to assess a crack initiation.•The criterion uses controlling quantity that plays key role in crack initiation process.•The criterion can be applied with various controlling quantities.•The approach contributes to more reliable assessment of components with stress concentrators. General singular stress concentrators often occur in engineering components and they represent places prone to crack initiation. Estimation of crack initiation conditions is usually performed by means of stability criteria of generalized fracture mechanics. These stability criteria require knowledge of asymptotic description of the stress state around the general singular stress concentrator. In cases of some concentrators, this analytical-numerical description can be quite difficult and does not belong among straightforward engineering approaches. This paper introduces an easy and engineering way to assess conditions for crack initiation and propagation in general singular stress concentrators using standard numerical approaches. The paper handles well-known criteria of generalized fracture mechanics of sharp and bi-material notches and simplifies them to a practical form usable for engineers. The resulting criterion fits the frame of criteria of finite fracture mechanics and extends their applicability.