### Methods  
Mechanical activation of Portland cement and cement-sand mortar was carried out in an installation for processing materials and activating mixing processes with simultaneous grinding of the material and its electromagnetic treatment with VLA [34]. The general view of the installation of the VLA of an industrial design is shown in Figure 1, and the technical characteristics of the VLA are presented in Table 7. Externally, the apparatus is an inductor placed in a case. A pipe made of non-magnetic material (working space) passes through the bore of the inductor. When electricity is supplied, a powerful rotating electromagnetic field is created in the working space, which rotates the ferromagnetic elements placed in it. The latter become magnets and interact with the main field. As a result of the interaction, a number of effects are generated that affect the substance placed in the workspace. These effects can include-magnetostriction, mechanostriction, cavitation, electrolysis, torsion fields, acoustic waves. The specific power of these effects is high. The consequence of this is considerable increases in the rates of physicochemical processes in substances placed in the working space of the installation. The methods pass from the diffusion to the kinetic level, and as a result of the opening of chemical radicals, the reaction rates increase hundreds of times. The mechanical activation process is carried out as follows. A chiller is fed into the unit's cooling system, then power is applied, and processing begins. Previously, ferromagnetic needles with a length of 20 \(\pm\) 2 mm are loaded into the working area, the diameter (\(d\)) of which is related to the length (\(l\)) in a ratio of 1:10 (\(l/d=10\)). This ratio is optimal for the activation of cement in terms of impact efficiency and is selected empirically. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Indicator Title** & **W/C** & **C, kg/m3** & **W, L/m3** & **CS, kg/m3** & **S, kg/m3** & \(\rho_{\text{cm}}\), kg/m3 \\ \hline Indicator value & 0.58 & 327 & 190 & 1315 & 573 & 2405 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Parameters of the composition of the concrete mixture. Figure 1: General view of the VLA installation: (**a**) installation in a protective case, connected to the water supply; (**b**) installation without a protective case, not connected to the water supply. It is known that the greatest dispersing effect is obtained with wet grinding, i.e., in the aquatic environment. This is due to the wedging effect of water molecules entering the pores and cracks of the solid. Therefore, when carrying out the study, we used grinding of components in an aqueous medium in the form of cement suspensions or solutions. At the first stage, studies of the dispersion characteristics of the cement paste processed in the VLA installation were carried out. In the experiment, the processing time of the cement paste in the VLA was varied in the range from 0 to 150 s. At the same time, the characteristics of the granulometric composition and the specific surface area of the cement particles were monitored. For particle size analysis, a Microsizer 201C laser particle analyzer was used. It is a fully automated device and is designed for fast and accurate measurement of particle size distribution in the range  
The PSKh-11 MSP device was used to control the specific surface area of the cement particles. The general view of the device is shown in Figure 3, and its technical characteristics are shown in Table 9.  
After processing in the VLA, 3 parts of standard sand (based on the mass of cement) were added to the resulting mixture, the mass was mixed in a laboratory concrete mixer for three minutes. Further, beams of a standard size (40 \(\times\) 40 \(\times\) 160 mm) were molded from the obtained cement-sand mortar. In total, 4 series of beams were made, 3 samples each. The samples hardened within 28 days under normal conditions (with a temperature of (20 \(\pm\) 2) \({}^{\circ}\)C and a relative humidity of (95 \(\pm\) 5)%).