Analysis of horizontal drainage well effect of improved saline soil based on Modflow-Hydrus coupling model
DAI Fenggang1,2,3, WANG Xiaoyan4*, GU Mingxu5, YU Wanlu1,2,3, LIAN Pengda1,2,3
1. Hebei Province Key Laboratory of Sustained Utilizationand Development of Water Resources, Hebei GEO University, Shijiazhuang, Hebei 050031, China; 2. Hebei Province Collaborative Innovation Center for Sustainable Utilization of Water Resources and Optimization of Industrial Structure, Hebei GEO University, China, Shijiazhuang, Hebei 050031, China; 3. Hebei Center for Ecological and Environmental Geology Research, Hebei GEO University, Shijiazhuang, Hebei 050031, China; 4. Hydrogeology and Environmental Geology Survey Center, China Geological Survey, Baoding, Hebei 071051, China; 5.Key Laboratory of Geological Resources and Environment Monitoring and Protection, Hebei Geological Environment Monitoring Institute, Shijiazhuang, Hebei 050021, China
Abstract：In order to improve the amelioration improvement level of saline-alkaline soil, and determine the scientific and reasonable design scheme of irrigation and drainage engineering, the Modflow-Hydrus coupling model of saturated -unsaturated soil water transport was established, and the drainage effect of horizontal wells in different scenarios in the test area was simulated and analyzed. The results show that: 1)when the depth of groundwater level is shallow, the seasonal variation has an obvious influence on the comprehensive recharge intensity of groundwater; when the groundwater depth is greater than 6 m, the comprehensive recharge intensity of groundwater tends to be constant in different periods; when the groundwater depth level is large, the precipitation supply through the thick vadose zone is uniform. When intermittent drainage occurs, the phreatic water level of a single horizontal well decreases significantly within the control range of 400 m, which has a good drainage effect. The drawdown is positively correlated with the annual pumping intensity of horizontal wells. Under the natural environment, the precipitation infiltration and phreatic water evaporation keep balance, and extend outward from the center of the test area. The drainage test can effectively improve the precipitation infiltration and phreatic evaporation environment within 8 times of the experimental area, so that the soil moisture in the vadose zone enters the saturated zone, and the phreatic water level shown a downward trend. The research results provide theoretical reference for horizontal well construction design of saline alkali soil improvement.
代锋刚,王晓燕*,谷明旭,余婉露,连鹏达,. 基于Modflow-Hydrus耦合模型的改良盐碱土水平井排水效果分析[J]. 排灌机械工程学报, 2021, (1): 61-67.
DAI Fenggang,WANG Xiaoyan*,GU Mingxu,YU Wanlu,LIAN Pengda,. Analysis of horizontal drainage well effect of improved saline soil based on Modflow-Hydrus coupling model. Journal of Drainage and Irrigation Machinery Engin, 2021, (1): 61-67.