An energy-based peridynamic model for fatigue cracking

Abstract

Fatigue design assessment is a crucial step in the design process of ships and offshore structures. To date, the stochastic approach is commonly used to calculate the total lifetime accumulated fatigue damage and the probability of fatigue failure for the structures. Meanwhile, the details of damage initiation and propagation are infrequently investigated. In terms of predicting crack growth, the traditional approaches face conceptual and mathematical difficulties in terms of predicting crack nucleation and growth, especially for multiple crack paths because the equations in classical continuum mechanics are derived by using spatial derivatives. Peridynamics is a non-local theory using the integral equations rather than differential equations which makes it suitable for damage prediction. In this study, a novel energy-based peridynamic model for fatigue cracking is proposed. The definition of cyclic bond energy release rate range and the energy-based peridynamic fatigue equations for both phases crack initiation and crack growth phases are introduced. For validation, first, a problem of mode-I fatigue crack growth is investigated. Next, different mixed-mode fatigue damages are also investigated and the peridynamic results are compared with the experimental results.

A criterion for dynamic ductile fracture initiation of tensile mode

“…Dynamic loading here and thereafter corresponds to non-cylic loading cases, that is, fatigue loading is beyond the scope of the current investigation and studied elsewhere (see e.g., Andreaus & Baragatti, 2012;Andreaus et al, 2017;Nguyen et al, 2020;Liao et al, 2020). The article is organized as follows.…”

A modified peridynamic method to model the fracture behaviour of nanocomposites

“…State-based peridynamics on the other hand describes materials with the energy absorbed among material points and are designed to address the aforementioned problems, i.e., without being limited to the tensile behaviour of brittle materials. Through the use of an energy-updating process, state-based peridynamics can be applied to both plastic behaviour [32] and damage behaviour under various loading conditions [33].…”

A Review of Peridynamics (PD) Theory of Diffusion Based Problems

“…Accordingly, literature concerning peridynamic theory is quite exhaustive and abundant. In the past two decades, several peridynamic studies pertaining to elastic deformation and fracture solids [2,[26][27][28], brittle fracture [29][30][31][32][33], fatigue failure [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49], and PD application of damage in composites [33,43,[50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65] have been reported. Studies related to crack initiation and propagation using peridynamics can be found in [30,[66][67][68][69].…”