技术报告-尾矿库设计及评估 (英文)(17)

技术报告-尾矿库设计及评估 (英文)

Design and Evaluation of Tailings Dams

Figure 6. Single (a) and Segmented (b) Ring-Dike Impoundment Configurations

(Source: Vick 1990)

According to Ritcey (1989), most recent dike dams have been built using downstream or centerline methods

rather than the upstream method (see below for descriptions of the various types of construction); Ritcey cites

Green (1980) as reporting that long-term stability of upstream dikes is not certain.

Embankments are required on all sides, so this method utilizes a large amount of embankment fill in relation

to the storage volume. This layout can be arranged in single or segmented form. The regular geometry

typically used with this configuration makes it amenable to the installation of various kinds of liners. (Vick

1990)

If the terrain is flat and thus suitable for ring-dikes, this configuration allows maximum flexibility in actually

selecting a site. Since the dikes are relatively low in height, the design is often simpler than a high valley dam

design. Containment can be achieved by using an impervious core in the dikes and/or the use of a liner below

the impoundment.

Unlike valley impoundments, which are located in a natural catchment area, the ring-dike design enables

better maintenance of water control. The quantity of pond water is limited to that transported with the

tailings and any precipitation falling directly onto the impoundment. There is no runoff other than from outer

slopes. Since surface runoff and flood impacts are reduced, a smaller pond area and/or less elaborate water

control measures are required. A trade-off can be made with a high tailings depth that reduces surface area