Groundwater Flow in Rock Mass at Deep Depth.

深层岩体中的地下水流。

• 批准号: 61550468
• 负责人: ESAKI Tetsuro
• 金额: $ 1.28万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61550468/
• 关键词: Permeability; Laboratory Test; Discontinuity; Shear; Joint; Rock Mass; Usage of Underground Space; 間隙水圧

The characteristics of the groundwater flow and the pore pressure in rock masses at deep depth are studied. The obtained results are as follows:(1) The triaxial confining condition is excellent for the permeability test of intact rocks whose permiability is more than 10^<-9> cm/sec. The flow rate usually decreases with time, due to blocking the pores in the rocks with small grains.(2)The pore pressure reduces the strength of porous rocks. The strength reduction of rocks with low porosity is also caused under greatly forced pore pressure.(3) The permeability testing apparatus apecially designed for jointed rocks can control the inlet and outlet pressures independently by a back pressure valve and can measure the amount of outflow correctly by electlonic balance-micro computer system.(4) The mismatched joint which shows low stiffness and dilatancy is more permeable than the matched joint. The permeability of these joints is much influenced by the confining pressure and pore pressure. Under high pressure gradient, the flow along such joints does not follow the Darcy's law.(5) The permeability model of mismatched joint must be considered as the flow through a system of tortuous and variable channels and the channel nature in fractures.

研究了深部地下水流特征和岩体孔隙压力。所得结果如下： (1)三轴约束条件对于渗透率大于10^-9 cm/sec的原岩渗透率测试具有良好的效果。由于小颗粒堵塞了岩石中的孔隙，流速通常随着时间的推移而减小。(2)孔隙压力降低了多孔岩石的强度。低孔隙率岩石的强度降低也是在较大的强制孔隙压力下造成的。 (3)专为节理岩石设计的渗透率测试装置，可通过背压阀独立控制入口和出口压力，并能正确测量流出量。 (4)失配接头具有低刚度和低剪胀性，比匹配接头具有更高的渗透性。这些节理的渗透性很大程度上受围压和孔隙压力的影响。在高压梯度下，沿此类节理的流动不遵循达西定律。(5)失配节理的渗透率模型必须考虑流经曲折多变的通道系统和裂缝中的通道性质。