Influences of height of leakage point on uncoordinated deformation of heightening canals in cold areas
GUO Wan-li1,2, CAI Zheng-yin1,2,*, WANG Yi3, HUANG Ying-hao1,2, ZHANG Chen2
1. Key Laboratory of Failure Mechanism and Safety Control Techniques of Earth-Rock Dam of the Ministry of Water Resources, Nanjing 210024, China; 2. Geotechnical Engineering Department, Nanjing Hydraulic Research Institute, Nanjing 210024, China; 3.College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling 712100, China;
Abstract: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.
郭万里, 蔡正银, 王羿, 黄英豪, 张晨. 渗漏点高度对寒区加高渠道不协调变形的影响[J]. 岩土工程学报, 2020, 42(s2): 100-105.
GUO Wan-li, CAI Zheng-yin, WANG Yi, HUANG Ying-hao, ZHANG Chen. Influences of height of leakage point on uncoordinated deformation of heightening canals in cold areas. Chinese J. Geot. Eng., 2020, 42(s2): 100-105.
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