Regulation of the temperature regime of concrete in the tiered technology of constructing an arch dam: Fid-Bau Portal

Regulation of the temperature regime of concrete in the tiered technology of constructing an arch dam

Gunter, Yu. S. / Danilov, A. S. / Red'kin, V. A. / Shchelkanova, M. V.

Conclusions 1. The possibility of constructing arch dams without cracks was proved by the experience of constructing the Miatla hydrostation. And prevention of cracking is achieved not by imposing more stringent requirements on the temperature regime and increasing the expenditures on its regulation but rather as a result of a fundamental change in the technology, which made it possible to reduce the cost of regulation in comparison with the traditional technology. 2. An increase of the allowable temperatures of the concrete mix to 23° and maximum temperature of the concrete to 45°, an increase of the cooling rate of concrete in the period after the temperature peak to 2°/day, and an increase of the rate of growth of the dam in height to 8 m/month were substantiated as a result of on-site investigations performed during construction of the Miatla dam. 3. With the tiered technology the time of covering the blocks, continuous pipe cooling, and insulation of the faces from temperature shock acquire main significance for preventing cracking. The experience of constructing the Miatla dam permits raising the question about removing restrictions on the rate of growth of the structure in height, temperature of the concrete mix, maximum temperature of the concrete, height of the blocks, cooling rate, and possibly the dimensions of the blocks in plan (within expedient limits) in the tiered technology of concreting with times of covering the blocks of less than 7 days with continuous intense pipe cooling in combination with insulation of the faces in the cold season.