In this study, electromagnetic (EM) radiation shielding of a clay composite with three different admixtures was tested. Because of the rapid development of new modern technologies, human exposure to non-ionizing EM radiation has grown exponentially. This has aroused the interest of scientists to answer the question of how long-term exposure to EM radiation is harmful to human health. Due to potential risks to human health and an increasing number of studies that have concluded that long-term EM radiation can be harmful to health, the WHO has classified the radiofrequency band (from 300 kHz to 300 GHz) as a potential cause of cancerous diseases. The frequency span 1.5-6 GHz was tested. Admixtures used as a partial replacement in mass percentage are fly ash, titanium dioxide and zinc ferrite. The percentage replacement was 5%. The results showed the lowest transmission in specimens with titanium dioxide addition. The lowest transmission in regards to the reference sample was about −10 dB. This research was done with the aim of production of load-bearing bricks with high protection against EM radiation for the construction of healthy buildings.

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Concrete with recycled rubber as a partial replacement of fine natural aggregate, intended for use in load-bearing structural elements, requires specific fresh concrete properties such as a particular slump and flow classes. These specific requirements can be caused by increased water or superplasticizer content. Therefore, concrete mixtures with different percentages of two types of superplasticizers A1 and A2, i.e. 0.2, 0.4 and 0.6% by cement mass, were prepared. Furthermore, the effect of retention of consistency after 15, 30, 45, 60, and 90 minutes, was also studied. Slump and flow table tests were performed at 15-minute intervals to determine the fresh performance of each concrete mixture and retention of consistency. Test results indicate that mixtures with superplasticizer A2 show a more uniform workability range during the measurement period and at the end of the measurement, remain within the same consistency classes, as in the initial measurement.