Modified concrete mixes to improve the performance and service life of 0.4–10 kV overhead line support posts

Introduction. The existing regulatory requirements for vibrated reinforced concrete support posts for overhead power lines (overhead lines) of 0.4–10 kV are analyzed. It is noted that the required frost resistance and waterproofness of concrete are insufficient and inadequate, as well as the crack resistance of reinforced concrete pillars exposed to changing seasonal operating conditions and aggressive environmental influences. Aim. The obtaining of optimal compositions and requirements for concrete mixtures for the manufacture of racks of the SV type. At the same time, the practical implementation of this goal will become the basis for the development of proposals for updating of existing regulatory documents in order to create uniform requirements for Rosseti Group of Companies and increase control over the products supplied by precast concrete plants. Materials and methods. The results of research aimed at the analysis of the possibility of using of the new materials in the manufacture of reinforced concrete products that enhance their performance and strength qualities, and at the same time improve the quality of concrete mixtures using domestic additives without significant increase of the cost of support posts such as SV 95 and SV 110. Results. According to the results of the above studies, the composition of the concrete mixture has been obtained, with the help of which it is possible to increase the operational and strength qualities of racks of the SV type, and, as a result, to increase their service life to the level of 50 years or more. The obtained research results will be taken into account when developing Technical Specifications for the production of racks of the SV type. Conclusions. Based on the obtained indicators of the optimal composition of the concrete mix, the specialists of Rosseti Scientific and Technical Center JSC developed design documentation for the pillars of SV 95-3,5, SV 110-5 and SV 110-7 for the purposes of manufacturing and conducting mechanical tests of prototypes of the pillars.