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Fortification structures, both military and civilian, are designed to resist a blast explosion to some extent. Their technical condition after a blast load must be assessed in a fast and reliable way to enable the users’ decision about the future use of the structure. Preferably, for the assessment of the protective structure, the non-destructive testing method should be used. To assess the suitability of ultrasound testing method for fortification structures built from steel fiber reinforced concrete, an investigation in a laboratory and in situ was conducted, together with numerical simulation and statistical evaluation. The numerical simulation of the blast load of a steel fiber reinforced concrete slab was conducted using multiphysics simulation software with the aim to verify basic parameters of the field experiment. During the field tests, several slabs were loaded by plastic explosive and changes in the structure of the slabs, before and after the blast load, were examined using the ultrasound pass-through method. After the field tests, the slabs were subjected to a destructive laboratory test to determine their residual strength. Subsequently, the data sets obtained from the measurements were tested using functional data analysis. The results from the ultrasound pulse method show that specimens after a dynamic blast load can in some cases increase the strength of their cement matrix.

This paper deals with analytical assessment of deflection od thick concrete slabs under shock and impact loading caused by the blast wave. The process started with the determination of the shock wave characteristics and the loading which the wave causes. Based on the experimental measurement, the peak was obtained. Subsequently, the reflected overpressure was calculated together with the transformation of the shock loading to quasi static loading. The experimental measurement to determine the strength of concrete of the concrete slab was carried out in the next step. Based on these input parameters, the deflection of the slab was calculated with analytical approach and compared with the experiment measurement, where both results show agreement. From the analytical assessment process, it can be concluded, that the analytically obtained results shows dependence on the input parameters mostly connected to the assessed material, therefore their determination is essential.

Recycled rubber materials are one of cheap and suitable materials for energy absorbers in protective structures. Standard tests of elastomers in uniaxial or biaxial tension is not suitable and efficient for energy absorbers made of recycled car tires. Simple compression test and simple impact test are described material properties from those tests are determined and compared with simulation in ANSYS/AUTODYN.

Steel fibre reinforced concrete is a widely used building material in the field of civil and military structures. To fully utilize its properties, it is very important to pay attention to the technological process of its production. The principle of steel fibre reinforced concrete consists in uniform distribution of steel fibres in the given volume of the structural element. The possibilities of checking uniformity are still discussed and examined in the field of NDT (non-destructive testing). The paper describes a radiographic NDT method allowing to evaluate the uniformity of steel fibre distribution in situ. The experiment results are compared with the results of testing performed using the standard destructive testing method.