The concretes used for transport infrastructure facilities are exposed to the active impact of corrosive environment; therefore, such concretes face raised demands as for water repellency, frost resistance and corrosion resistance. These properties can be improved due to the use of additives that have a different kind of effect. This research paper gives consideration to the influence of added highly-dispersed chalk on the physical and mechanical properties of concrete, in particular, water repellency and frost resistance. Experimental data show that the doping of highly-dispersed chalk results in a reduced water repellency and an increased frost-resistance of concrete. The basic physical and mechanical properties of concretes depend on the structure with a special particle packing of the matrix in the interlayers between the structure –forming elements of each level. Assumingly, the influence of added highly-dispersedchalk on the water-repellency and frost-resistance of pavement concrete is conditioned by the optimal arrangement of chalk particles (matrix particles) in the interlayers between the cement particles and the filler (structure-forming elements).

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In this paper, we consider a detailed technological process for manufacturing parts, namely, a gear wheel. The proposed method with the intervention of modern 3D modelling makes it possible to improve the main indicators of quality and strength of parts. Based on the results obtained, a cycloid transcendental system of circular motion of a gear wheel with the specified basic parameters was modelled. Using multifunctional modules, we studied the vibrations of the gear wheel at different points in time. It was found that due to the fatigue and contact strength, it is possible to ensure uniform flexural strength of the gear teeth. And also, by adjusting the profile of the teeth of the part, we selected the desired strengthening coefficient. The presented dependence of the angles of inclination of the gear teeth on the transformation coefficient allows you to improve the main indicators of quality and strength by at least 2 %.

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