International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Comparison of numerical methods for modeling the impact of an explosion on a metal plate such as LOAD_BLAST; LOAD_BLAST_ENHANCED; Arbitrary Lagrangian-Eulerian; Particle Blast Method; Smooth Particle Hydrodynamics which are implemented in the program LS-DYNA. The adequacy and accuracy of these methods are evaluated depending on the distance ratio to the explosive charge. The advantages and disadvantages of each method and recommendations for their use based on the results of this modeling and the experience of the authors of thisarticleare presented..

The experiment report presents the results of the field tests of fiber-reinforced concrete (FRC) and reinforced concrete specimens which were performed by research team from Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic in cooperation with the Czech Army corps in the military training area Boletice. The tests were performed using real scale reinforced concrete precast slabs (6×1.5×0.3m) with varying fibre content, fibre type, fibre strength and concrete strength class and 25 kg of TNT charges placed at a distance from the slab for better simulation of real in-situ conditions. The slabs were recorded using a high speed framing camera during the blast loading. The instrumentation enabled us to study the propagation of the blast shock wave through the material, propagation of the cracks on the soffit of the specimen and the final collapse of the middle part of the slab exposed to blast loading. The sequence of the structural behaviour is documented in detail and verified by numerical modelling using the LS-DYNA solver.

Field tests of fiber-reinforced concrete (FRC) and reinforced concrete specimens were performed by research team from Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic in cooperation with University and the Czech Army corps in the military training area Boletice. The test were performed using real scale reinforced concrete precast slabs (6 x 1.5 x 0.3m) with varying fiber type, fiber strength, fiber content and concrete strength class. TNT charges of 25kg placed at distance from the slab for better simulation of real in-situ conditions. The paper presents conclusions from sets of tests from 2016 and three previous in 2010, 2011 and 2013. Eleven specimens were tested in total. Two specimens were without fibres and had different concrete strength. Polypropylene fibres (PP) with length 50mm and strength of 600MPa and steel fibers (FE) with low ductility 25mm long and strength 400MPa were added in different content (0.5% and 1%) to the other nine specimens.

The paper describes the process of determining the blast load on structures and provides a numerical example of a fictive structure exposed to this load. The aim was to become familiar with the issue of blast load because of ever growing terrorist threat and the lack of guidelines from national and European regulations on the verification of structures exposed to explosions. The blast load was analytically determined as a pressure-time history.