Energy dissipation devices for structures under blast

Abstract

Terrorism pose a serious threat nowadays and many countries have the concern of protecting his people and most important buildings. This concern is an opportunity to strengthen the research of the behaviour of buildings under blast in order to reduce the magnitude of the effects of these catastrophic events. The present thesis aims to create a functional system to improve the security of critical buildings, either new or adapting old buildings to receive this new system. This system also tries to be cost efficient, so this can be used in most buildings. This thesis was centred in one system with two variations. The systems had the same lower reinforced concrete slab with 2,60 x 2,00 m and 0,12 m of thickness. The first system consisted in using 32 steel tubes of 76,1 mm outer diameter arranged uniformly and eight concrete panels, each one with 1,00 x 0,65 m and 0,07 m of thickness, on top of these tubes. The second system was the same concrete panels on top of 32 steel tubes with 48,3 mm outer diameter. To test these systems four blast trials were prepared: the first is the reference specimen and the other two using the two mentioned variations of the system. These slabs were tested simply supported in two parallel edges, with a span of 2,30 m. In all tests 6,00 Kg of the explosive Eurodyn 2000 were used at a distance of 1,85 m from the top of the slab to the centre of the explosive. The results show an improvement in the residual deformation and on the opening of the visible cracks of the base reinforced concrete slab.