List of Journal Publications
2013
6.
Vandoren, B., Proft, K. De, Simone, A., Sluys, L. J.
Mesoscopic modelling of masonry using weak and strong discontinuities Journal Article
In: COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING, vol. 255, pp. 167–182, 2013.
Abstract | BibTeX | Tags: Damage, GFEM, Masonry, Mesoscopic model, Partition of unity, Weak discontinuities | Links:
@article{Vandoren2013a,
title = {Mesoscopic modelling of masonry using weak and strong discontinuities},
author = {B. Vandoren and K. De Proft and A. Simone and L. J. Sluys},
doi = {10.1016/j.cma.2012.11.005},
year = {2013},
date = {2013-01-01},
journal = {COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING},
volume = {255},
pages = {167–182},
publisher = {ELSEVIER SCIENCE SA},
abstract = {A mesoscopic masonry model is presented in which joints are modelled by weak and strong discontinuities through the partition of unity property of finite element shape functions. A Drucker-Prager damage model describes joint degradation whereas the bricks remain linear elastic throughout the simulations. Analogies and differences amongst strong and weak discontinuity models are discussed, with special emphasis on kinematic description and implementation. Mesh sensitivity and performance of the presented models are illustrated by two-brick, three-point bending and shear wall tests.},
keywords = {Damage, GFEM, Masonry, Mesoscopic model, Partition of unity, Weak discontinuities},
pubstate = {published},
tppubtype = {article}
}
A mesoscopic masonry model is presented in which joints are modelled by weak and strong discontinuities through the partition of unity property of finite element shape functions. A Drucker-Prager damage model describes joint degradation whereas the bricks remain linear elastic throughout the simulations. Analogies and differences amongst strong and weak discontinuity models are discussed, with special emphasis on kinematic description and implementation. Mesh sensitivity and performance of the presented models are illustrated by two-brick, three-point bending and shear wall tests.
2007
5.
Duarte, C. A., Reno, L. G., Simone, A.
A high-order generalized FEM for through-the-thickness branched cracks Journal Article
In: INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, vol. 72, no. 3, pp. 325–351, 2007.
Abstract | BibTeX | Tags: Branched crack, Generalized element method, High-order finite elements, Hp-method, Partition of unity, X-FEM | Links:
@article{Duarte2007,
title = {A high-order generalized FEM for through-the-thickness branched cracks},
author = {C. A. Duarte and L. G. Reno and A. Simone},
doi = {10.1002/nme.2012},
year = {2007},
date = {2007-01-01},
journal = {INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING},
volume = {72},
number = {3},
pages = {325–351},
abstract = {This paper presents high‐order implementations of a generalized finite element method for through‐the‐thickness three‐dimensional branched cracks. This approach can accurately represent discontinuities such as triple joints in polycrystalline materials and branched cracks, independently of the background finite element mesh. Representative problems are investigated to illustrate the accuracy of the method in combination with various discretizations and refinement strategies. The combination of local refinement at crack fronts and high‐order continuous and discontinuous enrichments proves to be an excellent combination which can deliver convergence rates close to that of problems with smooth solutions.},
keywords = {Branched crack, Generalized element method, High-order finite elements, Hp-method, Partition of unity, X-FEM},
pubstate = {published},
tppubtype = {article}
}
This paper presents high‐order implementations of a generalized finite element method for through‐the‐thickness three‐dimensional branched cracks. This approach can accurately represent discontinuities such as triple joints in polycrystalline materials and branched cracks, independently of the background finite element mesh. Representative problems are investigated to illustrate the accuracy of the method in combination with various discretizations and refinement strategies. The combination of local refinement at crack fronts and high‐order continuous and discontinuous enrichments proves to be an excellent combination which can deliver convergence rates close to that of problems with smooth solutions.
2006
4.
Simone, A., Duarte, C. A., der Giessen, E. Van
A Generalized Finite Element Method for polycrystals with discontinuous grain boundaries Journal Article
In: INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, vol. 67, no. 8, pp. 1122–1145, 2006.
Abstract | BibTeX | Tags: Extended Finite Element Method, generalized finite element method, Grain boundary sliding, Partition of unity, polycrystals | Links:
@article{Simone2006,
title = {A Generalized Finite Element Method for polycrystals with discontinuous grain boundaries},
author = {A. Simone and C. A. Duarte and E. Van der Giessen},
doi = {10.1002/nme.1658},
year = {2006},
date = {2006-01-01},
journal = {INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING},
volume = {67},
number = {8},
pages = {1122–1145},
abstract = {We present a Generalized Finite Element Method for the analysis of polycrystals with explicit treatment of grain boundaries. Grain boundaries and junctions, understood as loci of possible displacement discontinuity, are inserted into finite elements by exploiting the partition of unity property of finite element shape functions. Consequently, the finite element mesh does not need to conform to the polycrystal topology. The formulation is outlined and a numerical example is presented to demonstrate the potential and accuracy of the approach. The proposed methodology can also be used for branched and intersecting cohesive cracks, and comparisons are made to a related approach (Int. J. Numer. Meth. Engng. 2000; 48:1741).},
keywords = {Extended Finite Element Method, generalized finite element method, Grain boundary sliding, Partition of unity, polycrystals},
pubstate = {published},
tppubtype = {article}
}
We present a Generalized Finite Element Method for the analysis of polycrystals with explicit treatment of grain boundaries. Grain boundaries and junctions, understood as loci of possible displacement discontinuity, are inserted into finite elements by exploiting the partition of unity property of finite element shape functions. Consequently, the finite element mesh does not need to conform to the polycrystal topology. The formulation is outlined and a numerical example is presented to demonstrate the potential and accuracy of the approach. The proposed methodology can also be used for branched and intersecting cohesive cracks, and comparisons are made to a related approach (Int. J. Numer. Meth. Engng. 2000; 48:1741).
2004
3.
Simone, A.
Partition of unity-based discontinuous elements for interface phenomena: Computational issues Journal Article
In: COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING, vol. 20, no. 6, pp. 465–478, 2004.
Abstract | BibTeX | Tags: Displacement discontinuity, Interface elements, Partition of unity | Links:
@article{Simone2004,
title = {Partition of unity-based discontinuous elements for interface phenomena: Computational issues},
author = {A. Simone},
doi = {10.1002/cnm.688},
year = {2004},
date = {2004-01-01},
journal = {COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING},
volume = {20},
number = {6},
pages = {465–478},
abstract = {The performance of partition of unity‐based discontinuous elements was studied by means of a numerical study. In particular, it was shown that conventional interface elements and partition of unity‐based discontinuous elements share the same structure of the stiffness matrix governing interface behaviour and, under specific circumstances, the same shortcomings (i.e. oscillations in the traction profile). The effect of various integration schemes on the interface contribution was studied through the analysis of a linear‐elastic notched beam. Further, an eigenvalue analysis of the partition of unity‐based discontinuous element was conducted to gain more insight into its mechanical behaviour.},
keywords = {Displacement discontinuity, Interface elements, Partition of unity},
pubstate = {published},
tppubtype = {article}
}
The performance of partition of unity‐based discontinuous elements was studied by means of a numerical study. In particular, it was shown that conventional interface elements and partition of unity‐based discontinuous elements share the same structure of the stiffness matrix governing interface behaviour and, under specific circumstances, the same shortcomings (i.e. oscillations in the traction profile). The effect of various integration schemes on the interface contribution was studied through the analysis of a linear‐elastic notched beam. Further, an eigenvalue analysis of the partition of unity‐based discontinuous element was conducted to gain more insight into its mechanical behaviour.
2.
Simone, A., Sluys, L. J.
The use of displacement discontinuities in a rate-dependent medium Journal Article
In: COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING, vol. 193, no. 27-29, pp. 3015–3033, 2004.
Abstract | BibTeX | Tags: Damage, Displacement discontinuities, Partition of unity, Plasticity, Rate dependence, Regularised continuum | Links:
@article{Simone2004b,
title = {The use of displacement discontinuities in a rate-dependent medium},
author = {A. Simone and L. J. Sluys},
doi = {10.1016/j.cma.2003.08.006},
year = {2004},
date = {2004-01-01},
journal = {COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING},
volume = {193},
number = {27-29},
pages = {3015–3033},
abstract = {This paper illustrates the use of displacement discontinuities in a rate-dependent elastoplastic-damage model. Rate-dependency is considered in the framework of Perzyna viscoplasticity. Displacement discontinuities are incorporated using the partition of unity property of finite-element shape functions. A combined continuous–discontinuous approach is proposed in which a discontinuity is only inserted after a certain amount of damage. Various examples illustrate the applicability of the combined approach to granular and quasi-brittle materials with and without fibre-reinforcement.},
keywords = {Damage, Displacement discontinuities, Partition of unity, Plasticity, Rate dependence, Regularised continuum},
pubstate = {published},
tppubtype = {article}
}
This paper illustrates the use of displacement discontinuities in a rate-dependent elastoplastic-damage model. Rate-dependency is considered in the framework of Perzyna viscoplasticity. Displacement discontinuities are incorporated using the partition of unity property of finite-element shape functions. A combined continuous–discontinuous approach is proposed in which a discontinuity is only inserted after a certain amount of damage. Various examples illustrate the applicability of the combined approach to granular and quasi-brittle materials with and without fibre-reinforcement.
2003
1.
Simone, A., Wells, G. N., Sluys, L. J.
From continuous to discontinuous failure in a gradient-enhanced continuum damage model Journal Article
In: COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING, vol. 192, no. 41-42, pp. 4581–4607, 2003.
Abstract | BibTeX | Tags: Damage, Discontinuities, Enriched finite-elements, Fracture, Gradient-enhanced continuum, Non-local continuum, Partition of unity | Links:
@article{Simone2003a,
title = {From continuous to discontinuous failure in a gradient-enhanced continuum damage model},
author = {A. Simone and G. N. Wells and L. J. Sluys},
doi = {10.1016/S0045-7825(03)00428-6},
year = {2003},
date = {2003-01-01},
journal = {COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING},
volume = {192},
number = {41-42},
pages = {4581–4607},
publisher = {Elsevier},
abstract = {A computational framework for the description of the combined continuous–discontinuous failure in a regularised strain-softening continuum is proposed. The continuum is regularised through the introduction of gradient terms into the constitutive equations. At the transition to discrete failure, the problem fields are enhanced through a discontinuous interpolation based on the partition of unity paradigm of finite-element shape functions. The inclusion of internal discontinuity surfaces, where boundary conditions are applied without modifications of the original finite-element mesh, avoids the unrealistic damage growth typical of this class of regularised continuum models. Combined models allow for the analysis of the entire failure process, from diffuse microcracking to localised macrocracks. The discretisation procedure is described in detail and numerical examples illustrate the performance of the combined continuous–discontinuous approach.},
keywords = {Damage, Discontinuities, Enriched finite-elements, Fracture, Gradient-enhanced continuum, Non-local continuum, Partition of unity},
pubstate = {published},
tppubtype = {article}
}
A computational framework for the description of the combined continuous–discontinuous failure in a regularised strain-softening continuum is proposed. The continuum is regularised through the introduction of gradient terms into the constitutive equations. At the transition to discrete failure, the problem fields are enhanced through a discontinuous interpolation based on the partition of unity paradigm of finite-element shape functions. The inclusion of internal discontinuity surfaces, where boundary conditions are applied without modifications of the original finite-element mesh, avoids the unrealistic damage growth typical of this class of regularised continuum models. Combined models allow for the analysis of the entire failure process, from diffuse microcracking to localised macrocracks. The discretisation procedure is described in detail and numerical examples illustrate the performance of the combined continuous–discontinuous approach.
