This paper deals with the description, measurement, and use of electromagnetic properties of ferromagnetic fibres used as dispersed fibre reinforcement in composite mixtures. Firstly, the fibres’ magnetic properties are shown, and a method of measuring the hysteresis loop of fibres is proposed. The results from the measurements are presented and a discussion of the influence of measured parameters on the fibres’ orientation in a magnetic field is performed. Furthermore, methods of non-destructive estimation, of their amount and orientation in the composite specimens, are discussed. The main experimental goal of this paper is to show the relationship between this non-destructive method’s results and the destructive flexural strength measurements. The method is sensitive enough to provide information related to fibre reinforcement.

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The static response of ballistic panels and also its resistance to blast and ballistic impact is investigated in the framework of this study. By connecting individual ballistic panels together, the protective barrier can be constructed. The protective barrier can be featured as a system with high mobility and versatility that is achieved by linking basic interlocking plate elements together. The resulting protective barrier can be shaped according to many possible scenarios in a wall with various possible opening angles and a small post with the tetragonal base or a larger post with the hexagonal ground plan. The material solution of the protective barrier benefits from the application of ultra-high-performance fibre-reinforced cement-based composites (UHPFRCC), which meets the requirements for enhanced resistance against extreme loads such as blast or impact. Besides, by using UHPFRCC, thin and slender design can be adopted, which is advantageous in many ways. Slender design results in a lower weight, allowing for easy manipulation and replacement. To verify the behavior of the panels, the proposed barrier was subjected to various loadings at different strain rates. The experimental campaign demonstrated that the protective barrier has a reasonable load-bearing capacity and also sufficient resistance against projectile impact and blast effects.

Ultra-high-performance steel-fibre-reinforced concrete (UHP-SFRC) is a technologically advanced composite with a high ability to absorb and dissipate mechanical energy. This work investigates the possibility of increasing ballistic resistance by adding different percentages of corundum and basalt aggregate into this type of concrete. The most common type of ammunition, a 7.62 mm × 39 mm calibre with a full-metal jacket and a mild-steel core (FMJ-MSC), was used to test all samples. The size of the damage and the mode of failure were determined using a 3D scanner operating on the principle of photogrammetry. The experimental campaign showed that the addition of basalt and, especially, corundum aggregate has a positive effect on ballistic resistance. In particular, the increase in compressive strength and the slight decrease in depth of penetration (DOP) was observed in the case of the usage of the corundum aggregate.