# Reinforced Concrete Building with IED Detonation: Test and Simulation
## 2 Test Description and Instrumentation  
In this context, the German Federal Office of Criminal Investigation (namely BKA), which is part of the Federal Ministry of the Interior, started a project in 2017 on the effects of IEDs on state security forces personnel. This project consisted of numerous tests carried out in Germany, with different types of explosive charges, with and without shrapnel, and at different targets. During the project, the BKA had the collaboration of the Centre of Excellence against Improvised Explosive Devices (C-IED COE), a member of the NATO Centre of Excellence community, to advise on the creation of the IEDs. The last phase of testing consisted of creating a reinforced concrete structure that reproduces a possible location where terrorists prepare their material and detonate them before counter-terrorism police can get in and arrest them. This phase was carried out at the Sierra del Retin maneuvering and firing range, Barbate, Cadiz, from 18 to 20 September 2018. The concrete structure was designed by the \"_Subdireccion General de Proyectos y Obras--DIGENIN\"_ (part of the Spanish Ministry of Defense), while the instrumentation, measurements and modeling were carried out by the staff of the E.T.S.I. Minas y Energia (Universidad Politecnica de Madrid--UPM). Finally, the explosive charges and their detonations were prepared by the Explosive Ordnance Disposal Section (SEDEX) of the Amphibious Mobility Group (GRUMA) of the Third Army (TEAR)--Marines in collaboration with personnel from NATO's Counter Improvised Explosive Devices Centre of Excellence (C-IED COE). The structure built ad hoc for the tests was made of reinforced concrete and consisted of a perimeter corridor and an interior room in which the IEDs were placed. The design of the structure was based on the project requirements suggested by the BKA. The original idea was to have brick enclosures, but these were going to be destroyed after each trial making the project unfeasible in terms of time and money. For this reason, the structure was redesigned with reinforced concrete walls, with greater thicknesses in the exterior walls than in the interior walls. Doors and windows were also aligned to improve the venting of the shock wave. CYPECAD code was used for the design, and it was developed under the Spanish Technical Building Code (CTE) based on Eurocodes required by the European Union. The ground plan dimensions of the structure are shown in Figure 1, with the height between the floor and ceiling of the structure equal to 3 m. The outer walls were built with a thickness of 40 cm while the inner walls were 30 cm thick and the roof slab 25 cm. The concrete used for both the walls and the roof slab had a nominal compressive strength of 40 MPa, a density equal to 2300 kg/m\({}^{3}\), a tensile strength of 3.5 MPa, an elastic modulus equal to 30.9 GPa and a 20 mm maximum aggregate size. The reinforcement of the structure, made of B-500 C corrugated steel, was equally distributed on both sides of the walls and the roof slab in both directions (vertical and horizontal). The vertical reinforced steel of outer walls was constructed with a 12 mm diameter rebar evenly spaced at 300 mm, while in the inner walls, the diameter of the rebar used was 10 mm spaced at 200 mm. The horizontal steel of the outer walls had a diameter equal to 8 mm spaced at 150 mm; although in the inner walls the diameter used was the same, the spacing was increased to 200 mm. The reinforcement of the roof was made symmetrically on both sides, the inside of the cubic where the detonation was located and the outside, using 12 mm diameter rebars with a square mesh of 150 mm on each side. In height, both reinforcements were 180 mm apart, with the thickness of the slab equal to 250 mm; therefore, a sufficient concrete layer was ensured on both sides. Finally, there was a perimeter reinforcement in all the joints between the walls and the roof, with 16 mm diameter rebars separated in height by 160 mm.