13th International Conference on Fracture June 16–21, 2013, Beijing, China -6- 4. Summary and conclusions In this paper a material structure of concrete is simulated by the Anm material model. A number of irregular shape particles are planted in a matrix, representing coarse aggregates in mortar. This material structure of concrete is then converted into a voxelized image. After that a random lattice mesh is made, and three types of lattice elements are identified, which represent aggregates, matrix and interface respectively. A uniaxial tensile test is set up and simulated by fixing all the lattice nodes at the bottom of the specimen and imposing a prescribed unit displacement onto all the nodes at the top. The lattice fracture analysis gives the stress-strain response and microcracks propagation, from which some mechanical properties such as Young's modulus, tensile strength and fracture energy can be predicted. The simulated mechanical properties of the numerical concrete specimen are quite reasonable, which is a positive evidence that proves the feasibility of the proposed modeling procedures. Acknowledgements This research was carried out under project number M83.1.12459 in the framework of the Research Program of the Materials innovation institute M2i (http://www.m2i.nl). Part of this work was sponsored by the European Union FP7 project CODICE (http://www.codice-project.eu). References [1] Qian, Z., Multiscale Modeling of Fracture Processes in Cementitious Materials, PhD thesis, Delft University of Technology, 2012 [2] Ngo, D. & Scordelis, A., Finite Element Analysis of Reinforced Concrete Beams, J Am Concr Inst, 1967, 64, 152-163 [3] Rashid, Y., Ultimate strength analysis of prestressed concrete pressure vessels, Nuclear Engineering and Design, 1968, 7, 334-344 [4] Schlangen, E. & van Mier, J., Experimental and numerical analysis of micromechanisms of fracture of cement-based composites, Cement and Concrete Composites, 1992, 14, 105-118 [5] Hrennikoff, A., Solution of problems of elasticity by the framework method, Journal of Applied Mechanics, 1941, 8, 169-175 [6] Ziman, J. M., Models of disorder: the theoretical physics of homogeneously disordered systems, Cambridge University Press, 1979 [7] Herrmann, H. J.; Hansen, A. & Roux, S., Fracture of disordered, elastic lattices in two dimensions, Phys. Rev. B, American Physical Society, 1989, 39, 637-648 [8] Burt, N. J. & Dougill, J. W., Progressive Failure in a Model Heterogeneous Medium, Journal of the Engineering Mechanics Division, 1977, 103, 365-376 [9] Schlangen, E., Experimental and Numerical Analysis of Fracture Processes in Concrete, PhD thesis, Delft University of Technology, 1993 [10]Qian, Z.; Schlangen, E.; Ye, G. & van Breugel, K., Prediction of Mechanical Properties of Cement Paste at Microscale, Materiales de Construccion, 2010, 60, 7-18 [11] Schlangen, E. & Qian, Z., 3D modeling of fracture in cement-based materials, Journal of Multiscale Modelling, 2009, 1, 245-261 [12]Garboczi, E., Three-dimensional mathematical analysis of particle shape using X-ray tomography and spherical harmonics: Application to aggregates used in concrete, Cement and Concrete Research, 2002, 32, 1621-1638
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