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Understanding the effects of blast generated by an accidental or a terroristic explosion nearby a critical structure is a main concern for the French Institute for Nuclear Safety (IRSN) and the French-German Research Institute of Saint Louis (ISL). Full-scale reactive phenomena are however seldomly compatible with long-term studies due to cost and regulation issues. Reduced scaled experimental work consequently represents an attractive alternative. Using small plastic explosive charges, blast effects in free-field or around various obstacles based on reference structures can be repeatedly examined, in order to provide the data necessary to develop simplified and numerical models. Following previous work on this topic by IRSN using a blast table and 42 g Hexomax® charges placed on its surface, ISL modified one existing blast pad to reproduce the same configuration at a double scale (333 g charges of Hexomax®). This study was conducted using a reference hemicylindrical obstacle, commonly encountered on industrial sites and also representative of certain transport containers. Numerous pressure sensors installed within the table or the pad thickness and on the surface of the hemicylinders provided the overpressure evolution for different values of the charge to obstacle distance. Explosive charges were ignited at distances up to 3.5 m/kg1/3 from the obstacle at ISL scale to extend the applicability domain of the model described in our previous document (Trélat et al. [18]) at a larger scale. The objective of this work is to assess not only blast effects on a potential target but also its capability to modify the blast propagation in its downstream space.
blast, hemicylinder, high explosive, Mach reflection, scaled experiments
[1] Cheval, K., Loiseau, O. & Vala, V., Laboratory scale tests for the assessment of solid explosive blast effects. Part I: Free-field test campaign. Journal of Loss Prevention in the Process Industries, 23(5), pp. 613–621, 2010. https://doi.org/10.1016/j.jlp.2010.05.001
[2] Cheval, K., Loiseau, O. & Vala, V., Laboratory scale tests for the assessment of solid explosive blast effects, Part II: Reflected blast series of tests. Journal of Loss Prevention in the Process Industries, 25(3), pp. 436–442, 2012. https://doi.org/10.1016/j. jlp.2011.11.008
[3] Trélat, S., Impact de fortes explosions sur les bâtiments représentatifs d’une installation industrielle, PhD Thesis, Université d’Orléans, France, 2006.
[4] Sochet, I., Blast Effects, Springer Verlag, 2018.
[5] Van Dorsselaer, N., Eveillard, S. & Trélat, S., Experiments and simulations of explo- sives: shock wave propagation around a convex structure. Proceedings of the Fifteenth International LS-DYNA® Users Conference, 2018.
F. Trélat, S., Sturtzer, M.-O., Eveillard, S., Eckenfels, D., Mory, J., Legendre, J.-F., Braina, & Soubiès, B., Strong explosion near a convex structure: a multi-scale experimental study. Proceedings of the Twenty-fifth International Symposium on Military Aspects of Blast and Shock, 2018.
[6] Trélat, S. & Sturtzer, M.-O., Predicting explosion and blast effects: a multi-scale experi- mental approach. International Journal of Safety and Security Engineering, 9(4). pp. 356–370, 2019. https://doi.org/10.2495/safe-v9-n4-356-370
[7] Kinney, G.F. & Graham, K.J., Explosive shocks in air, Springer Verlag, 1985.
[8] TM5-1300, Technical Manual, Structures to Resist to the effects of Accidental Explosions, November, 1990.
G. Duong, D.H., Hanus, J.L., Bouazaoui, L., Pennetier, O., Moriceau, J., Prod’homme, & Reimeringer, M., Response of a tank under blast loading - part I: experimental characterization of blast loading arising from a gas explosion. European Journal of Environmental and Civil Engineering, 16(9), pp. 1023–1041, 2012. https://doi.org/10. 1080/19648189.2012.699741
[9] Glasstone, S & Dolan, P.J., (3rd edition), The effects of nuclear weapons, Available from US Government Printing Office, 1962.
[10] Drikakis, D., Ofengeim, D., Timofeev, E. & Voionovich, P., Computation of non-sta- tionary shockwave/cylinder interaction using adaptive-grid methods. Journal of Fluids and Structures, 11(6), pp. 665–692, 1997. https://doi.org/10.1006/jfls.1997.0101
[11] Takayama, K. & Kawauchi, T., The transition from regular to Mach reflection in truly non-stationary flows. Journal of Fluid Mechanics, 100, pp. 147–160, 1979. https://doi. org/10.1017/s002211208000105x
[12] Sturtzer, M.-O., Trélat, S. & Sinninger, L., Investigation on the post-processing of blast loading characteristics along a convex structure, submitted to the Sixteenth Interna- tional Conference on Structures under Shock and Impact, 22–24 June, Lisbon, Portu- gal, 2020.
[13] Grégoire, Y., Etude expérimentale et numérique de la dispersion explosive et de la com- bustion de particules métalliques, PhD Thesis, Ecole Nationale Supérieure de Méca- nique et d’Aérotechnique, France, 2009.
[14] Trélat, S., Sturtzer, M.-O., Eckenfels, D., Mano C., Braina F. & Legendre J.-F., High explosives blast propagation along a hemi-cylindrical obstacle: influence of pressure gauge technology on the overpressure characteristics, submitted to the Twenty-sixth International Symposium on Military Aspects of Blast and Shock, 15–20 November, Wollongong, Australia, 2020 (postponed).
[15] UFC 3-340-02, Structures to resist the effects of accidental explosions, Department of Defense USA, 2008.
[16] Trélat, S., Sturtzer, M.-O. & Eckenfels, D., Multi-scale experimental study of blast propagation around a hemi-cylindrical barrier. WIT Transactions on the built environ- ment, 198, pp. 53–64, 2020, ISSN: 1743-3509.
[17] https://www.pcbpiezotronics.fr/produit/capteur-de-pression/113b28/
[18] https://www.pcbpiezotronics.fr/produit/capteur-de-pression/m102a05/
[19] Dewey J.M., 53 Years of Blast Research – A Personal History, Proceedings of the Twenty-first International Symposium on Military Aspects of Blast and Shock, 2010.
[20] Genetier, M., Lefrançois, A., Suarez, J., Necysyn, N., Lavayssiere, M. & Baudin, G., Secondary shock measurement comparison and validation to implement the post-com- bustion model, Proceedings of the Twenty-fifth International Symposium on Military Aspects of Blast and Shock, 2018.
[21] Gavart, R., Trélat, S., Sturtzer, M.-O. & Eckenfels, D., Study of the propagation of blast waves generated by plastic explosives around hemicylindrical obstacles, ISL report R-04/16/03/000/0/00-00/RE-189/2020.