XI International Conference on Computational Plasticity Fundamentals and Applications

1. COMPLAS XI 7-9 September 2011 Barcelona - Spain MultiscaleModelling of Masonry Structures under Extreme Loading B A Izzuddin and L Macorini XI International Conference on Computational Plasticity Fundamentals and Applications Department of Civil and Environmental Engineering Imperial College London, UK

2. Outline • Advanced models for brick-masonry • Multiscale modelling approaches • 3D mesoscale model for nonlinear analysis • Domain partitioning approach • Conclusions MultiscaleModelling of Masonry Structures under Extreme Loading 2/23

3. Advanced models for brick-masonry • Macroscale model • Equivalent material approach Structural scale Mesoscale scale • Mesoscale model • Two-material approach Microscale scale MultiscaleModelling of Masonry Structures under Extreme Loading 3/23

4. Advanced models for brick-masonry • Macroscale model • Equivalent material approach Identification of material properties for macro-model MultiscaleModelling of Masonry Structures under Extreme Loading 4/23

5. Multiscale approaches for masonry • Homogenisation approach Homogenisation Basic cell (RVE) Homogenised continuum • Nested multiscale - FE2 • approach (Massart, 2007) MultiscaleModelling of Masonry Structures under Extreme Loading 5/23

6. Multiscale approaches for masonry FE2 approach Not effective for representing masonry when: • complex texture (multi-leaf masonry etc.) • the characteristic length of FEs at structural scale and RVE linear dimension are close MultiscaleModelling of Masonry Structures under Extreme Loading 6/23

7. Mesoscale partitioned modelling An advanced 3D mesoscale model incorporated into a multi-scale formulation • Structural scale • Mesoscale • Partitioning approach with macro-elements for masonry • Parallel computing • 3D brick/2D interface elements MultiscaleModelling of Masonry Structures under Extreme Loading 7/23

8. Mesoscale partitioned modelling An advanced 3D mesoscale model incorporated into a multi-scale formulation MultiscaleModelling of Masonry Structures under Extreme Loading 8/23

9. 2D nonlinear interface element • s C • s • st • s • Gf,I • s • s • uz • sc 3D mesoscale model for nonlinear analysis under extreme loading • Multi-surface nonassociated • plasticity • Geometric nonlinearity • s • t • Gc • t • s<0 • s • uz Compression test • t • stanf • Gf,II • s Shear test • ux(y) MultiscaleModelling of Masonry Structures under Extreme Loading 9/23

10. 3D mesoscale model for nonlinear analysis under extreme loading In-plane behaviour Vermeltfoort AT, Raijmakers TMJ (1993) mortar interface pv=0.3 MPa brick interface mortar interface J4D J5D MultiscaleModelling of Masonry Structures under Extreme Loading 10/23

11. In-plane behaviour Vermeltfoort AT, Raijmakers TMJ (1993) Wpl1 Wpl1 pv=0.3 MPa Wpl1 Wpl1 Wpl2 3D mesoscale model for nonlinear analysis under extreme loading J4D J5D MultiscaleModelling of Masonry Structures under Extreme Loading 11/23

12. In-plane behaviour Vermeltfoort AT, Raijmakers TMJ (1993) Wpl1 3D mesoscale model for nonlinear analysis under extreme loading Wpl2 Nonlinear Analysis of Masonry Structures using Mesoscale Partitioned Modelling 12/23

13. Out-of-plane behaviour Chee Liang, N.G. (1996) 3D mesoscale model for nonlinear analysis under extreme loading Wpl1 Wpl1 Wpl1 MultiscaleModelling of Masonry Structures under Extreme Loading 13/23

14. Mesoscale analysis of large specimens Gattesco, Macorini, Noè(2008) 3D mesoscale model for nonlinear analysis under extreme loading MultiscaleModelling of Masonry Structures under Extreme Loading 14/23

15. Partitioning approach: full coupling MPI Communication between parent structure and partitions MultiscaleModelling of Masonry Structures under Extreme Loading 15/23

16. Domain partitioning approach Performance of domain partitioning approach Accuracy of the method Monoliticmodel Model with partitioning Number of nodes for the parent structure and for each partition MultiscaleModelling of Masonry Structures under Extreme Loading 16/23

17. Domain partitioning approach Detailed analysis of large structures 162840 nodes – 62 partitions MultiscaleModelling of Masonry Structures under Extreme Loading 17/23

18. Partitioning approach: reduced coupling • Reduced freedoms at parent level via master-slave coupling • Reduced parent computation and communication MultiscaleModelling of Masonry Structures under Extreme Loading 18/23

19. Effectiveness of reduced coupling mod1 mod2 MultiscaleModelling of Masonry Structures under Extreme Loading 19/23

20. Effectiveness of reduced coupling pv Fh 4 partitions Time Elastic analysis mod1 58.56 s mod2 40.59 s MultiscaleModelling of Masonry Structures under Extreme Loading 20/23

21. Effectiveness of reduced coupling Plastic work (interfaces) at peak load pv Fh mod1 mod2 4 partitions Time Nonlinear analysis mod1 1303.9 s mod2 978.59 s MultiscaleModelling of Masonry Structures under Extreme Loading 21/23

22. Conclusions • Accurate multiscale numerical method for brick-masonry using domain partitioning at structural scale with an accurate model at mesoscale • Effectiveness of developed partitioning method compared to monolithic approach demonstrated by significant speed-up and computational feasibility • Developed partitioning method maintains similar accuracy of detailed monolithic mesoscale method even with the reduced coupling approach MultiscaleModelling of Masonry Structures under Extreme Loading 22/23

23. Acknowledgements • 7th European Community Framework Programme, Marie Curie Intra-European Fellowship • High Performance Computing Services, • Imperial College London MultiscaleModelling of Masonry Structures under Extreme Loading 23/23

24. COMPLAS XI 7-9 September 2011 Barcelona - Spain MultiscaleModelling of Masonry Structures under Extreme Loading B A Izzuddin and L Macorini XI International Conference on Computational Plasticity Fundamentals and Applications Department of Civil and Environmental Engineering Imperial College London, UK