杨房沟水电站河谷边坡岩体渗透性统计分析  

A Statistical Analysis of Permeability about the Rock Mass in Valley Slope of Yangfanggou Hydropower Station

作　　者：徐海亮[1] 程龙[1] 林太清[1] 胡杨[1] 荣冠[1,2] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072 [2]武汉大学水工岩石力学教育部重点实验室,武汉430072

出　　处：《中国农村水利水电》2015年第6期99-104,共6页China Rural Water and Hydropower

基　　金：国家重点基础研究发展计划("973"计划)项目(2011CB013501;2010CB732005);新世纪优秀人才计划项目(NCET-11-0406)

摘　　要：为了研究杨房沟水电站河谷边坡岩体的渗透性规律,根据杨房沟水电站坝址区的钻孔压水试验资料,统计分析了坝址区河谷边坡岩体渗透性随深度的变化规律。现场试验表明河谷区岩体渗透性为:弱风化上段和下段岩体所处的岩层为弱透水层,微新岩体所处的岩层为微透水层。对所选钻孔的压水试验数据进行分析得出:在整体上,河谷边坡岩体的渗透性变化规律表现为随着河谷边坡岩体风化卸荷程度的增加渗透系数成逐渐增大的趋势;在垂直方向上,坝址区边坡岩体的渗透系数随着深度的增加成负指数衰减,并且随着卸荷风化程度的减小衰减系数也相应减小。在弱风化上段和下段,岩体的渗透性主要受风化和卸荷作用控制,渗透系数较大;在微新岩体段,由于风化卸荷作用的减小,自重应力成为渗透性的主要控制因素;在水平方向上,同一高程处渗透系数随距离河床中心线的水平埋深的增大而减小,服从负指数衰减规律。In this paper ,the law of permeability in different depths of rock mass stratum is studied by analyzing the dates of borehole water pressure test in dam site of Yangfanggou Hydropower Station .Permeability classification of the rock mass for the study area is that the permeability of weak weathering section is weak permeable and the permeability of lightly weathering and new section is mi‐cro-permeable .It is found out that the hydraulic conductivity has close relationship with the extension of unloading and weathering of rock mass .Vertically ,the hydraulic conductivity decreases exponentially with the increasing depth of rock mass in the valley slope . Meanwhile ,the attenuation coefficient decreases with the lower degree of weathering in rock mass .Thus it can be inferred that the permeability of rock masses in the valley slope is controlled by weathering and unloading in weak weathering section and the gravity stress becomes the uppermost factor of the permeability in lightly weathering and new section .Horizontally ,in the same elevation the relationship between hydraulic conductivity and horizontal depth is also negative exponential .

关 键 词：杨房沟水电站 河谷边坡 渗透性 负指数衰减 

分 类 号：TU45[建筑科学—岩土工程]