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Abstract. The use and the combination of new, high efficient materials for crashworthiness is of great interest nowadays. Foamed materials are commonly used to increase efficiency of composite materials. Based on the results obtained by Brachos and Douglas, it can be concluded that the sum of the energy absorption capabilities of the foamed filling and unfilled composite tubes is smaller than the energy absorbed by the tubes filled with the same filling. The paper presents the results of the experimental investigations into the influence of filling the tubes with different materials on the impact energy absorption capability. The tube shaped specimens made of epoxy composite, reinforced with carbon or glass fabrics were filled with foamed aluminium or foamed poly(vinyl chloride). It was proved that the foamed materials increase the energy absorption and the absorbed energy of the tubes filled with foams is greater than the sum of the energy absorbed by the composite tube without filling and the foamed material itself investigated separately, when the wall thickness is more than 2 mm. The investigations of the filled tubes with the thickness of walls equal to 1 mm showed lower absorbed energy values because the crushing force had decreased during the crush. The investigations were executed to show what are the effects of filling composite energy absorbing elements in the shape of tubes with foamed materials. Additionally, influence of tube wall thickness and crush mechanism were studied.

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The paper presents the methodology of numerical modelling of road crash tests based on the selected vehicle-road barrier system using the possibilities of modern CAD /CAE computing systems for a numerical simulation process of the collision. Owing to these systems, thorough analysis of the process of collision, including the analysis of the stress and strain fields and energy consumption in the tested systems, is possible. It is possible to design and redesign virtually the barriers at a relatively low cost.Streszczenie: W artykule przedstawiono metodykę modelowania numerycznego drogowych testów zderzeniowych na przykładzie wybranego układu pojazddrogowa bariera ochronna, z wykorzystaniem możliwości nowoczesnych systemów obliczeniowych CAD/CAE do numerycznej symulacji przebiegu zderzeń. Dzięki wykorzystaniu tych systemów możliwa jest dogłębna analiza procesu zderzenia, w tym analiza pól naprężeń, odkształceń oraz energochłonności badanych układów. Możliwe jest wirtualne projektowanie i przeprojektowywanie barier przy relatywnie niskich kosztach.Słowa kluczowe: zderzenie, LS-DYNA, PN-EN 1317, metoda elementów skończonych

Abstract. In the work, the attempt to determine the influence of loading rate on temperature of the surface of the crushed composite energy absorbing elements was undertaken. The specimens made of epoxy composites reinforced with glass fabrics and carbon fabrics of the structures [(0/90)T ]n were subjected to dynamic investigations. Thermovision investigations were conducted during energy absorbing tests. A thermovision camera enables the measurement of the temperature on the whole surface of the specimen visible in the camera lens while the measurement with the use of thermocouple is only local and has great heat inertia. During the investigations, the increase of specimen temperature related to impact velocity occurs. The temperature increase is caused by friction between the particles of the crushed specimen and by friction between the specimen and the support of the strength machine. At high loading rates, the increase of temperature on the surface of the specimens was significantly greater than the softening temperature of the epoxy resin E-53.