Justification of the effectiveness of the Proletarian main canal during reconstruction

Abstract

Calculations of the main parameters of the Proletarsky main canal for a polygonal section during its reconstruction for various options are presented. A method for hydraulic calculation of the Proletarsky main canal has been carried out. The developed method of the hydraulic calculation is based on the determination of the coefficient of reduction of the polygonal shape of the section to the trapezoidal one according to the formula of A.A. Uginchus. Then the cross-sectional area of each element is found after reduction to a trapezoidal section, the wetted perimeters, hydraulic radius and Shezi coefficient of each section element are calculated. For the earthen channel of the canal, the obtained hydraulic characteristics closely matched the design data for the flow rate and average current velocity. The earthen channel of the canal with an ice cover has a significant decrease in hydraulic parameters from the design section, both in terms of flow rate up to 36.0 m³/s (or by 33%) and in terms of the average flow velocity up to 0.410 m/s. The widened asymmetrical earthen channel is characterized by an increased discharge up to 57.47 m³/s, an effective cross-section of 101 m² and a wetted perimeter of 42.0 m in comparison with the design section. For the channel of the canal section with a protective strengthening made of a rock fill and gravel-pebble coating, reduced characteristics were obtained both in terms of flow rates and average flow rates which is due to their high value of roughness coefficients. At the same time, it was found that a decrease in the roughness coefficients of protective coatings during operation due to the colmatage of alluviums particles will lead to an increase in water consumption in the canal. However, the process of alluviums colmatage of the protective layer of stone material will be slow, for 10 years or more.