Active Anti-Seepage and Passive Anti-Seepage in Geomembrane Anti-Seepage

  Geomembrane can be used for anti-seepage function at the bottom of reservoirs. The role of anti-seepage mainly includes controlling water leakage, thereby ensuring the stability of buildings and preventing waste of water loss. Geomembrane anti-seepage can be divided into two forms: active anti-seepage and passive anti-seepage according to different functions. When leakage control requirements are not strict and there is no direct impact on the safe operation of related buildings, a passive anti-seepage scheme can be adopted. Reservoir bottom anti-seepage systems usually adopt passive anti-seepage schemes, and the reasons for this are as follows:
  1. The upper reservoir has a large water catchment area and large average natural water flow. The upper limit of concentrated leakage at reservoir bottom faults is high. Therefore, leakage control is not its main function. Its main role is to reduce the possible adverse effects of vertical fault leakage on plants, reduce the seepage gradient in fault channels, and reduce the risk of seepage damage.
  2. Reservoir bottom fault leakage water directly infiltrates into underground areas through reservoir bottom mountain faults. After anti-seepage treatment, the main building of the upper reservoir can meet its own operational safety.
  3. Geomembrane anti-seepage scheme. Geomembrane anti-seepage adopts the "front block and rear leak" method, that is, setting curtain grouting around the geomembrane and setting a drainage system under the membrane. From the perspective of anti-seepage effect and operational safety, it is an ideal solution.
  4. The geomembrane in the project is connected with the surrounding reservoir bank slabs to form a reliable closed system. In the upper reservoir of the project, the geomembrane is only closely attached to the south bank of the reservoir and closed with dams and bank slabs. The layout conditions of the entire anti-seepage structure vary greatly. Therefore, considering the following factors comprehensively, a semi-closed non-drainage system is selected for the anti-seepage scheme.