Finite Cell Method implementation and validation of a nonlocal integral damage model

Enthalten in
International journal of mechanical sciences 
Volume
128-129
Start Page
401
End Page
413
Citation
International Journal of Mechanical Sciences (128-129): 401-413 (2017-08)
Publisher DOI
10.1016/j.ijmecsci.2017.05.008
Scopus ID
2-s2.0-85019695965
In this paper, the Finite Cell Method is further developed for a nonlocal damage problem. This method is a combination of a fictitious domain approach with higher-order finite elements, adaptive integration, and weak enforcement of the non-conforming essential boundary conditions. The fictitious domain approach alleviates the urge for boundary conforming meshes that are usually time-consuming to be generated free of error in case of geometrically complex structures. The ductile damage constitutive model used is a thermodynamically consistent nonlocal theory of integral type in which the damage variable is integrated over the whole domain. The formulation is implemented in a high-order finite element package tailored for the Finite Cell Method. The experiments are performed on a test specimens made of the aluminum alloy AA-7075-T6 to validate the results of our numerical approach. A good agreement of the simulation and experimental testing has been achieved. The efficiency of the method is then investigated with a numerical study of a porous domain with a more complex geometry. Further it is demonstrated that the nonlocal damage model compared to the local models, studied earlier by the authors, performs better in terms of convergence and numerical stability.
Schlagworte
AA-7075-T6
Ductile fracture
Finite Cell Method
Nonlocal integral damage mechanics