Observational study on rainwater infiltration into a mountain

山区雨水入渗观测研究

• 批准号: 06650574
• 负责人: SHIMOJIMA Eiichi
• 金额: $ 1.22万
• 依托单位: Daido Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650574/
• 关键词: rain-infiltration; fractured sedimentary rocks; mountain tunnel; seepage; water quality; CO_2 gas; observation; 山体トンネル湧水

Through continuous monitoring of seepage into a tunnel in a mountain composed of sedimentary fractured rocks and CO_2 gas concentraiton (C_<co2>) within the tunnel, the following is disclosed : (1) Increase in the discharge of seepage water (Q) owing to rainfall was observed to be faster than that in C_<co2>, when Q was large. Comparing a theoretical analysis with the observed result, it was concluded that, when C_<co2> shows a peak value, a slowly infiltrating component (matrix flow) begins to contribute to the seepage discharge. Pore-airs with high concentration of CO_2 gas near the ground surface are transported downwards by movement of the matrix flow. These ascertain the existence of two infiltration components called 'fissure flow' and 'matrix flow' which occur in relatively large and small voids of fractured rocks base, respectively. Overall, information of CO_2 gas concentraiton is useful for understanding the infiltration process. (2) A detected quite good correspondence of variation in the electrical conductivity of seepage water to that in C_<co2> is based on the chemical process that, the concentraiton of HCO_3^- (dominant anion) changes with varying C_<co2> in void-airs via dissolution/degassing.

本文通过对沉积裂隙岩体中隧道渗流及洞内CO_2气体浓度（C_2）的连续监测<co2>，揭示了：（1）当Q较大时，降雨引起的渗漏水流量（Q）的增加比C_2的增加快<co2>;通过理论分析和实测结果的比较，得出当C_1<co2>出现峰值时，缓慢入渗组分（基质流）开始对渗流量产生贡献的结论。近地表的高浓度CO_2气体通过基质流的运动向下输送。这确定了存在两个渗透成分，称为“裂隙流”和“基质流”，分别发生在相对较大和较小的孔隙裂隙岩石基地。总之，CO_2气体浓度的信息是有用的了解渗透过程。(2)渗透水电导率变化与C_2电导率变化有较好的对应关系，这是<co2>由于孔隙气中主导阴离子HCO_3^-浓度随C_2变化而<co2>发生溶解/脱气的化学过程。

项目成果

Y.Ueda, E.Shimojima, R.Yoshioka, T.Tanaka & Y.Hoso: "Rain-infiltration into a mountain and behaviors of CO_2 gas" Proc.Ann.Conference, JSCE. (in press). (1996)

Y.Ueda、E.Shimojima、R.Yoshioka、T.Tanaka

下島栄一: "亀裂堆積岩の山体での雨水浸透とその水質" 水工学論文集(土木学会). 1995 (39)

Eiichi Shimojima：“裂隙沉积岩山体中的雨水渗透及其水质”水利工程学报（日本土木工程师学会）1995（39）。

E.Shimojima, Y.Ueda, T.Tanaka & Y.Hoso: "Rain-infiltration into a fractured sedimentary rock mountain and its water quality." Ann.J.Hydraulic Eng., JSCE. 39. 325-330 (1995)

E.下岛、Y.Ueda、T.Tanaka

下島栄一・吉岡龍馬: "山体トンネルの湧水と炭酸ガス濃度の変化の関係" 土木学会中部支部研究講演会概要集. 209-210 (1996)

Eiichi Shimojima和Ryoma Yoshioka：“山隧道中的泉水与二氧化碳浓度变化之间的关系”日本土木工程师学会中部分会研究会议摘要209-210（1996）。

上田裕一朗・下島栄一・吉岡龍馬: "山体トンネルの湧水の変化と炭酸ガス濃度の変化の関係" 土木学会中部支部研究発表会講演概要集. 209-210 (1996)

Yuichiro Ueda、Eiichi Shimojima、Ryoma Yoshioka：“山间隧道中泉水变化与二氧化碳浓度变化之间的关系”日本土木工程师学会中部分会的演讲摘要 209-210 (1996)。