Influences of height of leakage point on uncoordinated deformation of heightening canals in cold areas

Due to the periodic changes of water supply and temperature in canals in high cold regions, the canal soils will undergo the "wetting-drying and freeze-thaw" cycles, which will aggravate the uncoordinated deformation of the heightening canals. The influences of different heights of leakage point on the uncoordinated deformation of canal slopes is analyzed by taking the heightening canal in northern Xinjiang as an example. The main conclusions are as follows: (1) The most significant uncoordinated deformation of the canal slopes occurs at the "freezing" stage, but it does not occur at the lowest temperature point, it occures when the temperature starts to rise from the lowest temperature. (2) When the leakage point is near the midpoint of the canal slopes, the uncoordinated deformation of the canal slopes caused by the addition of high rise is the most significant. The distance between the canal slope and the linings is the maximum, which increases with the increasing number of "wetting-drying and freeze-thaw" cycles to a constant value. (3) When the seepage point is higher than the midpoint of the canal slopes, the frost-heave deformation of the canal slopes increases, but the distance between the canal slopes and the linings caused by the uncoordinated deformation decreases. When the seepage point is lower than the midpoint of the canal slopes, the frost-heave deformation and the uncoordinated deformation of the canal slopes are both lower. It can be seen that a larger frost heave in the canal slopes does not necessarily mean a larger uncoordinated deformation in the heightening canals. When the leakage point is lower, the frost heave is the minimum and the uncoordinated deformation caused by heightening layer is also the minimum, which is an ideal working condition.