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Techniques for numerical simulations of concrete slabs for demolishing by blasting / A. Plotzitza in Journal of engineering mechanics, Vol. 133 N°5 (Mai 2007) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 133 N°5 (Mai 2007) . - pp.523–533. Titre : Techniques for numerical simulations of concrete slabs for demolishing by blasting Type de document : texte imprimé Auteurs : A. Plotzitza, Auteur ; T. Rabczuk, Auteur ; J. Eibl, Auteur Année de publication : 2007 Article en page(s) : pp.523–533. Note générale : Applied mechanics Langues : Anglais (eng) Mots-clés : Concrete  slabs  Blasting  Strain  rate  Constitutive  equations  Simulation  models  Numerical  analysis  Experimental  data Résumé : The subject of this article is the numerical simulation of concrete under explosive loading using a meshbased and a meshfree discretization technique. The presented techniques are verified by experimental data. Experimental evidence suggests that the complete stress–strain history relation must be considered as a basis for constitutive modeling if concrete is subjected to high loading rates. These dynamic phenomena cause a retardation of damage activation which must be taken into account when constitutive modeling is pursued on mesolevel instead of microlevel. By including a dynamic relaxation formulation within the framework of a general three-dimensional coupled continuum damage-plasticity law, it is shown that the solution of the wave propagation problem in materials with strain-softening becomes independent of mesh size. As the simulation of concrete under contact detonation causes severe numerical problems because of the large deformations, special numerical spatial discretization techniques have to be used. In this article we compare the results of a concrete slab under contact detonation using the finite element method code LS-DYNA with an arbitrary Lagrangian Eulerian coupling and the results obtained by a MLSPH code developed at our institute with experimental data. The same constitutive model for concrete and the same equation of state for the explosive is implemented in the two codes. The results of the different numerical simulations and the experimental data agree with each other well. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%290733-9399%282007%29133%3A5%2852 [...] [article] Techniques for numerical simulations of concrete slabs for demolishing by blasting [texte imprimé] / A. Plotzitza, Auteur ; T. Rabczuk, Auteur ; J. Eibl, Auteur . - 2007 . - pp.523–533. Applied mechanics Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 133 N°5 (Mai 2007) . - pp.523–533. Mots-clés : Concrete  slabs  Blasting  Strain  rate  Constitutive  equations  Simulation  models  Numerical  analysis  Experimental  data Résumé : The subject of this article is the numerical simulation of concrete under explosive loading using a meshbased and a meshfree discretization technique. The presented techniques are verified by experimental data. Experimental evidence suggests that the complete stress–strain history relation must be considered as a basis for constitutive modeling if concrete is subjected to high loading rates. These dynamic phenomena cause a retardation of damage activation which must be taken into account when constitutive modeling is pursued on mesolevel instead of microlevel. By including a dynamic relaxation formulation within the framework of a general three-dimensional coupled continuum damage-plasticity law, it is shown that the solution of the wave propagation problem in materials with strain-softening becomes independent of mesh size. As the simulation of concrete under contact detonation causes severe numerical problems because of the large deformations, special numerical spatial discretization techniques have to be used. In this article we compare the results of a concrete slab under contact detonation using the finite element method code LS-DYNA with an arbitrary Lagrangian Eulerian coupling and the results obtained by a MLSPH code developed at our institute with experimental data. The same constitutive model for concrete and the same equation of state for the explosive is implemented in the two codes. The results of the different numerical simulations and the experimental data agree with each other well. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%290733-9399%282007%29133%3A5%2852 [...]