Applications of lattice method in the simulation of crack path in heterogeneous materials
Journal Title: Frattura ed Integrità Strutturale - Year 2015, Vol 9, Issue 34
Abstract
The simulation of critical and subcritical crack propagation in heterogeneous materials is not a simple problem in computational mechanics. These topics can be studied with different theoretical tools. In the crack propagation problem it is necessary to lead on the interface between the continuum and the discontinuity, and this region has different characteristics when we change the scale level point of view. In this context, this work applies a version of the lattice discrete element method (LDEM) in the study of such matters. This approach lets us to discretize the continuum with a regular tridimensional truss where the elements have an equivalent stiffness consistent with the material one wishes to model. The masses are lumped in the nodes and an uni-axial bilinear relation, inspired in the Hilleborg constitutive law, is assumed for the elements. The random characteristics of the material are introduced in the model considering the material toughness as a random field with defined statistical properties. It is important to highlight that the energy balance consistence is maintained during all the process. The spatial discretization lets us arrive to a motion equation that can be solved using an explicit scheme of integration on time. Two examples are shown in the present paper; one of them illustrates the possibilities of this method in simulating critical crack propagation in a solid mechanics problem: a simple geometry of grade material. In the second example, a simulation of subcritical crack growth is presented, when a pre-fissured quasi-brittle body is submitted to cyclic loading. In this second example, a strategy to measure crack advance in the model is proposed. Finally, obtained results and the performance of the model are discussed.
Authors and Affiliations
L. Kosteski, F. Soares, I. Iturrioz
Keywords
Related Articles
- EP ID EP128001
- DOI 10.3221/IGF-ESIS.34.24
- Views 76
- Downloads 0
Gradient-enriched linear-elastic tip stresses to perform the highcycle fatigue assessment of notched plain concrete
Gradient Elasticity (GE) allows the stress analysis to be performed by taking into account the size of the dominant source of microstructural heterogeneity via a suitable length scale parameter. This is done by s...
Study of the influence between the strength of antibending of working rolls on the widening during hot rolling of thin sheet metal
Based on the variation principle of Jourdan was developed a mathematical model of the process of widening freely in hot rolling of thin sheet metal. The principle applies to rigid-plastic materials and for the ci...
Evaluation of stress intensity factor of multiple inclined cracks under biaxial loading
A finite rectangular plate of unit thickness with two inclined cracks (parallel and non parallel) under biaxial mixed mode condition are modelled using finite element method. The finite element method is used for d...
Multi-challenge aspects in fatigue due to the combined occurrence of multiaxiality, variable amplitude loading, and size effects
The three major issues which contribute to uncertainties in fatigue life estimations are the limited transferability of material data obtained in a laboratory for describing the fatigue behavior of components, the...
Valutazione della capacità di rientro alla base di un elicottero in presenza di danno balistico ad un albero di trasmissione della linea rotore di coda
Nella progettazione di un elicottero militare, destinato ad operare a bassa quota e in ambiente ostile, il danneggiamento di componenti critici, conseguente ad impatto balistico, riveste un ruolo primario nella valutazio...