PSI - Issue 13

Tuan Duc Le et al. / Procedia Structural Integrity 13 (2018) 1702–1707 T.D. Le, P. Lehner, P. Konečný / Structural Integrity Procedia 00 (2018) 000 – 000

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4. Results and Conclusions

This study is just an initial attempt to create a 2D chloride ingress model of heterogeneous RC structures via specific example of a RC beam. The model was set up with the combination of random fields and 2 nd Ficks Law of diffusion under the scheme of FEM. The adopted procedure is able to address the heterogeneity as indicated in Fig. 1 (b) by non-parallel isolines of chloride concentration. However, the spatial variability in considered example describes the larger area of concrete specimen such as clusters of aggregates and matrix. The meso-structure diffusion model suitable for the comparison of numerical model with the results of LIBS 2D images was not achieved. Acknowledgements This contribution has been developed as a part of the research project GACR 18- 07949S “Probabilistic Modeling of the Durability of Reinforced Concrete Structures Considering Synergic Effect of Carbonation, Chlorides and Mechanical Action” supported by the Czech Grant Agency . Financial support for research results dissemination of Ministry of Education Youth and Sports of the Czech Republic via project Funding Multilateral Scientific and Technological Cooperation Projects in the Danube Region No: 8X17039 is highly appreciated. AASHTO-T259, 2012. 02 Standard Method of Test for Resistance of Concrete to Chloride Ion Penetration . Washington, D.C.: American Association of State Highway and Transportation Officials. Ba žant, Z.P., Vořechovský, M., Novák, D., 2007. Asymptotic Prediction of Energetic -Statistical Size Effect from Deterministic Finite-Element Solutions. “ Journal of Engineering Mechanics ” 133(2), 153 – 62. Cusatis , G., Bažant, Z., Cedolin, L., 2003. Confinement -Shear Lattice Model for Concrete Damage in Tension and Compression: II. Computation and Validation. “ Journal of Engineering Mechanics ” 129(12), 1449 – 58. http://ascelibrary.org/doi/10.1061/%28ASCE%290733 9399%282003%29129%3A12%281449%29. Cusatis, G., Cedolin, L., 2007. Two- Scale Study of Concrete Fracturing Behavior. “ Engineering Fracture Mechanics ” 74(1– 2), 3 – 17. Cusatis, G., Pelessone, D., Mencarelli, A., 2011. Lattice Discrete Particle Model (LDPM) for Failure Behavior of Concrete. I: Theory. “ Cement and Concrete Composites ” 33(9), 881 – 90. Eliáš, J., Vořechovský, M., Skoček, J., Bažant, Z.P., 2015. Stochastic Discrete Meso -Scale Simulations of Concrete Fracture: Comparison to Experimental Data. “ Engineering Fracture Mechanics ” 135, 1 – 16. Ghosh, P., Konečný, P., Lehner, P., Tikalsky, P.J., 2017. Probabilistic Time -Dependent Sensitivity Analysis of HPC Bridge Deck Exposed to Chlorides. “ Computers and Concrete ” 19(3), 305 – 13. Gottlieb, C., Millar, S., Günther, T., Wilsch, G., 2017. Revealing Hidden Spectral Information of Chlorine and Sulfur in Data of a Mobile Laser Induced Breakdown Spectroscopy System Using Chemometrics. “ Spectrochimica Acta - Part B Atomic Spectroscopy ” 132, 43 – 49. Grassl, P., Bažant, Z.P ., 2009. Random Lattice-Particle Simulation of Statistical Size Effect in Quasi-Brittle Structures Failing at Crack Initiation. “ Journal of Engineering Mechanics ” 135(2), 85 – 92. http://ascelibrary.org/doi/10.1061/%28ASCE%290733 9399%282009%29135%3A2%2885%29. Grassl, P., Grégoire, D., Rojas Solano, L., Pijaudier-Cabot, G., 2012. Meso-Scale Modelling of the Size Effect on the Fracture Process Zone of Concrete. “ International Journal of Solids and Structures ” 49(13), 1818 – 27. http://dx.doi.org/10.1016/j.ijsolstr.2012.03.023. Herrmann, H.J., Hansen, A., Roux, S., 1989. Fracture of Disordered, Elastic Lattices in Two Dimensions. “ Physical Review B ” 39(1), 637 – 48. Hooton, R.D., Thomas, M.D.A., Standish, K., 2001. Prediction of Chloride Penetration in Concrete. , 412. https://trid.trb.org/view.aspx?id=690787. Jiang, W., Shen, X., Xia, J., Mao, L., Yang, J., Liu, Q., 2018. A Numerical Study on Chloride Diffusion in Freeze-Thaw Affected Concrete. References