Designs of air curtains for the arch dams of the Chirkey and Miatla hydroelectric stations

Conclusions

It can be concluded from the design studies of the creation of air curtains for the Chirkey and Miatla hydrostations that in reality it is possible to provide reliability of dams already constructed in regions where the design seismicity was increased by constructing an air curtain.

One can, of course, also reduce the hydrostatic load on the dam by reducing the elevation of the reservoir. However, then the reduction of the storage capacity of the reservoir and decrease of head worsen the power capabilities of the hydrostation by an amount far exceeding the expenditures related to creating the air curtain. For example, the one-time expenditures on creating the air curtain for the Chirkey hydrostation in 1984 prices are 10 million rubles, whereas a reduction of the normal pool level would lead to underproduction of energy amounting to about this sum every year.

The second direction is the provision of the design seismicity of a dam under construction (planned). Then in the case of using an air curtain it is possible to construct a dam with smaller volumes of concrete.

In the case of a gravity dam, this is 5–10% of the total volume of concrete, whereas the planned stationary air curtain for the Miatla hydrostation cost only about 1 million rubles in 1984 prices.