Technology of pipe refrigeration for the Krasnoyarsk hydroelectric station dam

Conclusions

• 1. Pipe network concrete-cooling systems for massive structures with a columnar block system can and should be used on a composite basis, i.e., not only for cooling concrete so as to create favorable conditions for joint grouting but also for relieving the thermal-stress condition of the blocks. This allows concreting of structures in blocks of great height.

• 2. The following conditions are essential for ensuring a successful composite utilization of the cooling system:

• a) The arrangement of the cooling-system components should be such that the communications necessary for the cooling operation can be prepared in advance, before placing concrete.

• b) The cooling system must be supplied by permanent pumping stations having a large power reserve, equipped with a reliable water intake, and located at sites which are convenient for effecting repairs and replacing plant units; in selecting the capacity of the pumps the water requirements to meet other technological needs should be taken into account.

• c) The clearance diagrams and the layouts of galleries and other cavities in the dam body should be fixed with due allowance for laying cooling-system communications therein; it is desirable to provide special galleries for geodetic observations.

• d) The nets and their connections should be of such construction as will ensure they can be safely laid during concreting of the blocks.

• 3. Where climatic conditions resemble those for the Krasnoyarsk hydroelectric station, cooling can be successfully accomplished with river water at natural temperature.

• 4. It is expedient to effect regulation of the cooling process, not by regulating the water discharge through the units, but by stage-by-stage hooking-up and disconnection of the supply therto.