Foreman's crack growth rate equation and the safety conditions of cracked structures

✍ Scribed by JoséMaría Mínguez

• Book ID: 103072724
• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 825 KB
• Volume: 48
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(94)90174-0

✦ Synopsis

The Foreman's crack growth rate equation is integrated for a finite cracked sheet, subjected to cycling loading, for which the established fracture mechanics theory has been taken as a starting point. Thus, the crack length is related to the number of loading cycles and it is possible to evaluate the final number of fatigue cycles at which the crack reaches the critical length and failure happens.

It is demonstrated that the Paris law is only a rough approach to the problem, for its results can be either on the safe side or well within the unsafe region, this being the reason why the Foreman's equation is necessary. This allows the designer to determine more accurately the inspection frequency needed by the structure in order to be safe during the last period of its life. Also the influence of the material properties on the process is studied, as well as the influence of the geometric parameters and of the loading conditions.