Calculation of the strength of power transmission poles made of modified birch and aspen wood

The article discusses various materials used for the production of power transmission poles. One of the promising materials for the manufacture of power transmission poles is modified wood obtained by uniaxial pressing. In terms of its performance, modified wood is significantly superior to natural wood. Depending on the type of raw materials and technologies, pressed wood can have different densities, which have a significant impact on the operational properties of power transmission poles. The achievement of the necessary strength indicators is achieved at the expense of an unjustified increase in the size of the cross-section of power transmission poles. Climatic factors influencing the service life of modified wood are considered. A constructive solution was adopted to connect the splice elements to a spike with fixing brackets, eliminating possible movements in all directions and preventing the possible rotation of the two constituent elements. As a result of the calculations carried out on the strength of the spliced elements of power transmission poles, it was found that the crosssectional dimensions of a beam made of modified birch and aspen wood, recommended by regulatory documents, are overestimated with the specified strength parameters. The optimal dimensions of the cross-section of the power line column have been determined, taking into account the harsh operating conditions during the cold season and a high degree of icing. The calculations performed make it possible to reduce the consumption of raw materials for the production of pressed wood is for birch and aspen wood. The production of power transmission poles from modified wood is a promising direction for the development of the production of power transmission poles.

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