考虑裂隙-岩块间水交换的单裂隙非饱和渗流影响因素分析  

Analysis of Influence Factors on Unsaturated Flow in a Single Fracture Considering Water Exchange Between Fracture and Matrix

作　　者：胡云进[1] 钟振[1] 张新海[1] 

机构地区：[1]浙江大学水工结构与水环境研究所,浙江杭州310058

出　　处：《应用基础与工程科学学报》2012年第6期1110-1117,共8页Journal of Basic Science and Engineering

基　　金：国家自然科学基金资助项目(50809059;51279177)

摘　　要：为了研究考虑裂隙-岩块间水交换时单裂隙非饱和渗流的影响因素,应用分形几何法生成裂隙开度分布,根据毛细吸持理论和入侵准则形成充水域,基于水量平衡方程,建立了能考虑裂隙-岩块间拟稳态水交换的单裂隙非饱和渗流分析模型.进行了不同岩块孔隙率、不同岩块渗透系数及不同岩块初始饱和度情况下的单裂隙非饱和渗流数值模拟,以单裂隙非饱和渗透系数为评价指标,分析了各因素的影响程度.结果表明:岩块孔隙率对裂隙渗透性影响甚微;岩块渗透系数和岩块初始饱和度对裂隙渗透性存在较大影响,岩块渗透系数越大,裂隙-岩块间的水交换越剧烈,裂隙渗透性变化越明显,裂隙非饱和渗透系数随岩块初始饱和度的变化而变化.因此,在岩块渗透性较好或裂隙与岩块干湿差别明显的情况下,不能忽略裂隙-岩块间的水交换.To investigate the influence factors on unsaturated flow in a single fracture considering water exchange between fracture and matrix,an analysis model for unsaturated flow in a single fracture with quasi-static water exchange between fracture and matrix under consideration was built up based on water conservation equation. Fracture aperture distribution ,was created with fractal geometry method and water filled area was obtained by using capillary theory. Numerical simulations for unsaturated flow in a single fracture under different porosity, permeability and initial saturation of the rock were conducted and each factor＇s effect was analyzed by using unsaturated permeability of fracture as evaluation index. The results showed that rock porosity had little effect on fracture＇s permeability, but both permeability and initial saturation of the rock had significant influence on fracture＇s permeability. The water exchange between fracture and matrix became more intense as rock permeability grow larger, the change of fracture＇s permeability also became more obvious, and unsaturated permeability of the fracture varied with initial saturation of the rock. Therefore, water exchange between ignored under condition of highly matrix is quite different. permeable rock or the water fracture and matrix can not be saturation between fracture and

关 键 词：水交换 单裂隙 岩块渗透系数 初始饱和度 

分 类 号：TV554[水利工程—水利水电工程]