Issue 35

S. Tarasovs et alii, Frattura ed Integrità Strutturale, 35 (2016) 271-277; DOI: 10.3221/IGF-ESIS.35.31 277 C ONCLUSION n this work a two-scale finite element model is proposed for the simulation of the fiber reinforced concrete failure. The model uses cohesive elements to simulate the cracking of the concrete matrix, whereas the bridging action of steel fibers is approximated by non-linear springs, connecting the nodes on the opposite faces of the crack. The stiffness of these non-linear spring elements directly takes into account the orientation of individual fibers and crack growth direction, allowing to model anisotropy of the fracture toughness of fiber reinforced concrete. The results of simulations show that the spatial distribution of fibers orientations may have substantial effect on the crack propagation direction. A CKNOWLEDGEMENT his work has been funded by the Latvian Ministry of Education and Science via project Nr. 214/2012. R EFERENCES [1] Jones, P.A., Austin, S.A., Robins, P.J., Predicting the flexural load–deflection response of steel fibre reinforced concrete from strain, crack-width, fibre pull-out and distribution data, Mater. Struct., 41 (2007) 449–463. [2] Kozicki, J., Tejchman, J., Effect of steel fibres on concrete behavior in 2D and 3D simulations using lattice model, Arch. Mech., 62 (2010) 465–492. [3] Cunha, V.M.C.F., Barros, J.A.O., Sena-Cruz, J.M., An integrated approach for modelling the tensile behaviour of steel fibre reinforced self-compacting concrete, Cem. Concr. Res., 41 (2011) 64–76. [4] Radtke, F.K.F., Simone, A., Sluys, L.J., A computational model for failure analysis of fibre reinforced concrete with discrete treatment of fibres, Eng. Fract. Mech., 77 (2010) 597–620. [5] Xu, X.-P., Needleman, A., Numerical simulations of fast crack growth in brittle solids, J. Mech. Phys. Solids, 42 (1994) 1397–1434. [6] Tarasovs, S., Zile, E., Tamuzs, V., Experimental and numerical investigation of steel fiber reinforced concrete fracture, Proc. of 19th European Conference on Fracture, Kazan, Russia, 26-31 (2012) 6. [7] Zīle, E., Zīle, O., Effect of the fiber geometry on the pullout response of mechanically deformed steel fibers, Cem. Concr. Res., 44 (2013) 18-24. [8] Zollo, R.F., Fiber-reinforced concrete: an overview after 30 years of development, Cem. Concr. Compos., 19 (1997) 107-122. [9] Ferrara, L., Ozyurt, N., Prisco, M., High mechanical performance of fibre reinforced cementitious composites: the role of “casting-flow induced” fibre orientation, Mater. Struct., 44 (2011) 109–128. [10] Barnett, S.J., Lataste, J.-F., Parry, T., Millard, S.G., Soutsos, M.N., Assessment of fibre orientation in ultra high performance fibre reinforced concrete and its effect on flexural strength, Mater. Struct., 43 (2009) 1009–1023. [11] Robins, P., Austin, S., Jones, P., Pull-out behaviour of hooked steel fibres, Mater. Struct., 35 (2002) 434–442. [12] Cunha, V.M.C.F., Barros, J.A.O. & Sena-cruz, J.M., Pullout Behavior of Steel Fibers in Self-Compacting Concrete, J. Mater. Civ. Eng., 22 (2010) 1–10. [13] Morton, J., Groves, G.W., The cracking of composites consisting of discontinuous ductile fibres in a brittle matrix- effect of fibre orientation, J. Mater. Sci., 9 (1974) 1436-1445. [14] Bruhwiler, E., Wittman, F. H., The wedge splitting test, a new method of performing stable fracture mechanics tests, Eng. Fract. Mech., 35 (1990) 117–125. [15] Robins, P., Austin, S., Jones, P., Spatial distribution of steel fibres in sprayed and cast concrete, Mag. Concr. Res., 55 (2003) 225–235. I T