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Civil-Comp Proceedings
ISSN 1759-3433 CCP: 75
PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON COMPUTATIONAL STRUCTURES TECHNOLOGY Edited by: B.H.V. Topping and Z. Bittnar
Paper 57
3D Simulation of Concrete Cracking: Probabilistic Formulation in a Parallel Environment C.N.M. Paz+, L.F. Martha+, E.M.R. Fairbairn*, J.L.D. Alves*, N.F.F. Ebecken* and A.L.G.A. Coutinho*
+Department of Civil Engineering and Technology Group on Computer Graphics, Pontifical Catholic University of Rio de Janeiro, Brazil
Full Bibliographic Reference for this paper
C.N.M. Paz, L.F. Martha, E.M.R. Fairbairn, J.L.D. Alves, N.F.F. Ebecken, A.L.G.A. Coutinho, "3D Simulation of Concrete Cracking: Probabilistic Formulation in a Parallel Environment", in B.H.V. Topping, Z. Bittnar, (Editors), "Proceedings of the Sixth International Conference on Computational Structures Technology", Civil-Comp Press, Stirlingshire, UK, Paper 57, 2002. doi:10.4203/ccp.75.57
Keywords: parallel processing, high performance computing, discrete cracking concrete, probabilistic crack approach, material heterogeneity, size effects, tensile strength domain, Monte Carlo method, non-linear analysis, finite elements.
Summary
This work presents a probabilistic crack approach (Rossi et al [1]), based on the
Monte Carlo method, that was recently implemented in a 3D fully parallelized finite
element code (Paz, [2]). The cracking scheme used is the discrete crack approach
introduced by means of 3D interface elements. In this approach the heterogeneity of
the material is taken into account by considering the properties (tensile strength,
Young Modulus, etc.) to vary spatially following a normal distribution determined
by the mean the standard deviation of the considered material properties.
![]() ![]() The stochastic process is introduced at the material local scale considering that cracks are created within the concrete with different energy dissipation depending on the spatial distribution of constituents and initial defects. The local material behavior in concrete is assumed to be a perfect elastic brittle behavior. This the random distribution of local cracking energies can be replaced by a random distribution of local strengths. Fracturing is modeled by 3D interface elements that are generated in a previously defined region within the mesh. The interface elements are triangular base prisms connecting adjacent faces of neighboring tetrahedra. These elements simulate crack opening through relative displacements between the triangular faces. The model is based on the assumption the some particularities of the cracking behavior of concrete, such as strain softening, cracking evolution, and size-effects are derived from the heterogeneous characteristics of the material.
The code achieved a very good level for both parallel performance and
vetorization. The most demanding routines, which implement the matrix-vector-
multiply computational kernel for the interface and tetrahedral elements, are "fully"
parallelized
Extensive use of element-by-element techniques within the computational kernels comprised in the iterative solution drivers provided a natural way for achieving high Flop rates and good parallel speed-up's. Furthermore, element-by-element techniques avoid completely the formation and handling of large sparse matrices. Therefore, the computational strategies presented herein provide a natural way to deal with more complex scenarios, particularly those involving three-dimensional problems. References
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