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Masonry walls are one of the most widely used constructive elements in buildings. They offer a cost-effective option and can satisfy many buildings requirements. However, their brittle composition leads them to generate high-speed debris under blast loads. Many casualties arise due to this kind of fragments. Strengthening of masonry walls is of much importance to increase safety inside the buildings. For this purpose, it is desirable to carry out field tests to assess the improvement of reinforcement measures, but the cost and complexity of these experiments can be very high. Therefore, numerical modelling is a good alternative to evaluate the behaviour of brick masonry walls under blast loads. Uncertainties in numerical modelling may be significant due to the composite nature of the reinforced masonry construction and the number of variables describing the constituent materials. In this work, a finite element simulation of a blast-loaded brick masonry wall validated with corresponding field tests is presented. A total of 24 brickwork masonry walls panels at full scale were tested in six different trials with explosives charges. In the configuration of each test, there was one unreinforced wall and three walls with different protective solutions. This paper focuses on the study of unreinforced walls. A 3D pure Lagrangian approach using LS-DYNA was developed with appropriate blast parameters derived from CONWEP, material models and suitable boundary conditions. Results of numerical modelling are compared in terms of wall displacement with the field data obtained in the trials. Study results show good agreement between the field test and the numerical modelling, demonstrating that the model is consistent and reliable.
explosive, FEM simulation, full-scale tests, masonry walls
[1] Draganić, H., Gazić, G., & Varevac, D., Experimental investigation of design and retro- fit methods for blast load mitigation–A state-of-the-art review. Engineering Structures, 190, pp. 189–209, 2019. https://doi.org/10.1016/j.engstruct.2019.03.088
[2] Goswami, A., & Adhikary, S.D., Retrofitting materials for enhanced blast performance of structures: Recent advancement and challenges ahead. Construction and Building Materials, 204, pp. 224–243, 2019. https://doi.org/10.1016/j.conbuildmat.2019.01.188
[3] Badshah, E., Naseer, A., Ashraf, M., Shah, F., & Akhtar, K., Review of blast loading models, masonry response, and mitigation. Shock and Vibration, 2017.
[4] D’Altri, A.M., Sarhosis, V., Milani, G., Rots, J., Cattari, S., Lagomarsino, S., ... de Miranda, S., Modeling strategies for the computational analysis of unreinforced masonry structures: Review and classification. Archives of Computational Methods in Engineering, pp. 1–33, 2019.
[5] Lantz, L., Maynez, J., Cook, W., & Wilson, C.M.D., Blast protection of unreinforced masonry walls: A state-of-the-art review. Advances in Civil Engineering, 2016, 8958429, 2016. https://doi.org/10.1155/2016/8958429
[6] Wei, X., & Stewart, M.G., Model validation and parametric study on the blast response of unreinforced brick masonry walls. International Journal of Impact Engineering, 37(11), pp. 1150–1159, 2010. https://doi.org/10.1016/j.ijimpeng.2010.04.003
[7] Kernicky, T.P., Whelan, M.J., Weggel, D.C., & Rice, C.D., Structural identification and damage characterization of a masonry infill wall in a full-scale building subjected to internal blast load. Journal of Structural Engineering, 141(1), D4014013, 2015. https://doi.org/10.1061/(asce)st.1943-541x.0001158
[8] Campidelli, M., Tait, M.J., El-Dakhakhni, W.W., & Mekky, W., Numerical strategies for damage assessment of reinforced concrete block walls subjected to blast risk. Engineer- ing Structures, 127, pp. 559–582, 2016. https://doi.org/10.1016/j.engstruct.2016.08.032
[9] Wang, M., Hao, H., Ding, Y., & Li, Z.X., Prediction of fragment size and ejection distance of masonry wall under blast load using homogenized masonry material properties. International Journal of Impact Engineering, 36(6), pp. 808–820, 2009. https://doi.org/10.1016/j.ijimpeng.2008.11.012
[10] Su, Y., Wu, C., & Griffth, M.C., Modelling of the bond–slip behavior in FRP rein- forced masonry. Construction and Building Materials, 25(1), pp. 328–334, 2011. https://doi.org/10.1016/j.conbuildmat.2010.06.021
[11] Abdulla, K.F., Cunningham, L.S., & Gillie, M., Simulating masonry wall behaviour using a simplified micro-model approach. Engineering Structures, 151, pp. 349–365, 2017. https://doi.org/10.1016/j.engstruct.2017.08.021
[12] Burnett, S., Gilbert, M., Molyneaux, T., Beattie, G., & Hobbs, B., The performance of unreinforced masonry walls subjected to low-velocity impacts: Finite element analysis. International Journal of Impact Engineering, 34(8), pp. 1433–1450, 2007. https://doi.org/10.1016/j.ijimpeng.2006.08.004
[13] Chiquito, M., López, L.M., Castedo, R., Pérez-Caldentey, A., & Santos, A.P., Behaviour of retrofitted masonry walls subjected to blast loading: Damage assessment. Engineer- ing Structures, 201, p. 109805, 2019. https://doi.org/10.1016/j.engstruct.2019.109805
[14] Chiquito, M., Castedo, R., Santos, A.P., López, L.M., & Pérez-Caldentey, A., Numerical modelling and experimental validation of the behaviour of brick masonry walls subjected to blast loading. International Journal of Impact Engineering, 148, p. 103760, 2021. https://doi.org/10.1016/j.ijimpeng.2020.103760
[15] Livermore Software Technology Corporation (LSTC). LS-DYNA Keyword User’s Manual - R11 2018:3186.
[16] Kingery, C.N. & Bulmash, G., Airblast Parameters from TNT Spherical Air Burst and Hemispherical Surface Burst. US Army Armament and Development Center, Ballistic Research Laboratory, 1984.