Unified Model of K Factor and Compliance Based on Energy Equivalence Principle

doi:10.3901/JME.2018.14.098

Abstract

Abstract: The expressions of K factor and compliance C of general cracked specimens are very different from each other, and the number of formula parameters of K factor andthe compliance C for some specimens are much more than six, this is not convenient for application. The acquisition of K factor andthe compliance C expression for nonstandard samples mainly adopts the regression and fitting methods, it is quite complicated. A unified model with only 2 or 3 parameters to predict K factor and compliance C for nine components with mode-I crack is proposed based on the Chen-Cai energy equivalence method. Verifications show that the unified model of K factor and compliance C is in good agreement with the formulas in references and the results from finite element analysis. The establishment of the unified model is simple and effective, and it is convenient for engineering application. Therefore, the novel method is convenient to obtain the semi-analytical expressions of K factor and C for cracked specimens.

Key words: compliance, energy equivalence principle, mode I crack, stress intensity factor, unified model

CLC Number:

O346

HE Yi, CAI Lixun, CHEN Hui. Unified Model of K Factor and Compliance Based on Energy Equivalence Principle[J]. Journal of Mechanical Engineering, 2018, 54(14): 98-106.

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