地下坝防治海水入侵的三维数值模拟与混合整数多目标优化  

Three-dimensional numerical simulation and mixed-integer multi-objective optimization for preventing seawater intrusion using subsurface dams

作　　者：尹吉娜 鲁春辉 沈城吉[1] 陈华伟 陈麟 YIN Jina;LU Chunhui;SHEN Chengji;CHEN Huawei;CHEN Lin(The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210024,China;Yangtze Institute for Conservation and Development,Hohai University,Nanjing 210024,China;Water Resources Research Institute of Shandong Province,Jinan 250013,China;China Geological Survey Shenyang Geological Survey Center,Shenyang 110000,China)

机构地区：[1]河海大学水灾害防御全国重点实验室,江苏南京210024 [2]河海大学长江保护与绿色发展研究院,江苏南京210024 [3]山东省水利科学研究院,山东济南250013 [4]中国地质调查局沈阳地质调查中心,辽宁沈阳110000

出　　处：《水利学报》2025年第1期106-116,共11页Journal of Hydraulic Engineering

基　　金：国家重点研发计划项目(2021YFC3200500);国家自然科学基金青年项目(52109080,42102294)。

摘　　要：滨海区因地下水过度开采而遭受海水入侵灾害。地下坝可有效阻止海水入侵,但坝体内陆侧会滞留大量地下咸水而影响正常开采。针对实际复杂水文地质条件下地下坝后咸水体回退过程不明、模型过于简化、修复策略单一等问题,本文提出了地下坝防治海水入侵的三维数值模拟与多目标智能优化耦合方法。选取山东省龙口市黄水河库区作为目标区域,创建了基于SEAWAT_V4的三维变密度地下水流及盐分运移模型,并将SEAWAT模型与改进的NSGA-Ⅱ深度耦合,以减少地下水抽咸注淡量和减缓海水入侵程度为两个冲突目标,建立了混合整数变量的海水入侵防治多目标智能优化模型。结果表明,龙口黄水河库区地下坝防治海水入侵的效果受地下坝位置、长度等多重因素显著影响;抽咸注淡可形成区域性水力屏障,有效清除坝后地下咸水,明显减缓海水入侵程度;同时,优化获取的帕累托最优前沿面能够提供分布良好且广泛的抽注策略,满足决策者的不同管理需求。Coastal areas suffer from seawater intrusion due to over-exploitation of groundwater resources.Subsurface dam can prevent seawater intrusion,but a large amount of saline water will be trapped at the landside of the dam.Due to unknown saltwater retreat mechanism,oversimplified models and single remediation strategy behind subsurface dams under complex hydrogeological conditions,this study proposes a method coupling 3D numerical simulation with multi-objective intelligent optimization for seawater intrusion control using subsurface dams.Taking the Huangshuihe Reservoir area of Longkou City in Shandong Province as a case study,a 3D variable-density groundwater flow and salt transport model was constructed using SEAWAT_V4.The SEAWAT_V4 model was then coupled with an improved NSGA-Ⅱ to establish a mixed-integer multi-objective intelligent optimization model to control seawater intrusion,considering two conflicting objectives of reducing the total amount of groundwater extraction-injection as well as minimizing seawater intrusion.The results show that effectiveness of controlling saltwater intrusion is remarkably affected by locations and lengths of the subsurface dam.Saltwater extraction and freshwater injection can form a regional hydraulic barrier,effectively remediate saline water at the landside of the dam,and significantly slow down the extent of seawater intrusion.The Pareto-optimal front obtained from the optimization framework provides a widely spread optimal saltwater extraction and freshwater injection strategies,which can meet different management needs of decision makers.

关 键 词：地下坝 海水入侵 地下水数值模拟 多目标优化算法 抽咸注淡 

分 类 号：TV138[水利工程—水力学及河流动力学]