Abstract: The degree of salinization is serious in the south of Xinjiang Uygur Autonomous Region. Due to the frost heaving and salt heaving damage of saline soil foundation, the stability of channel slope in irrigation area is greatly damaged. A mathematical model of optimizing channels with quadratic parabolic cross section on saline soil was established using artificial atomic algorithm to avoid the problems of redundant calculation, large cumulative error and low precision by using iterative calculation method. The mathematical model used quadratic parabolic shape parameters as independent variables and was given channel bottom slope and roughness. According to the ratio coefficient between the optimal hydraulic section and the quadratic parabolic practical economic section of medium and small channels, the shape parameters were optimized by this algorithm to determine the practical economic section of the channel. The mathematical model was applied to Xiaosi branch canal in Tarim irrigation area of Xinjiang to verify the validity. Compared to the trial algorithm, this method was more suitable for the section optimization design of small and medium-sized channels. The calculated flow error was only 0.85% of the error of the trial algorithm. The results showed that the concrete quantity of parabola shaped optimization section was reduced by 3.34%.

Key words: channel, quadratic parabola, artificial atomic algorithm, hydraulic optimal section, practical economic section