| 摘要 |
FIELD: hydraulic engineering, exploitation of dams under rigorous climate conditions. SUBSTANCE: concrete dam includes internal part, external parts, heat insulation coat of its downstream face and tubular heat exchangers positioned in tiers. Tubular heat exchangers of downstream face are connected to pipe-lines supplying and carrying away heat transfer agent and function with formation of heated zone at downstream face of dam. Width of tier of tubular heat exchangers of dam in cross-section exceeds width of its downstream part in point of location of this tier or is equal to it and distance in height between tiers equals height of concrete block or is present integral number of times in this height. Dam is erected by casting concrete mixture in the form of concrete blocks and their subsequent cooling with the aid of tubular heat exchangers placed in concrete blocks with formation of tiers. Heat engineering parameters of heat exchangers, outlines of their tiers in plan and distance between tiers are set in compliance with assumed temperature condition in zone heated during period of exploitation of dam formed by downstream face of dam. Height of concrete blocks is set equal to distance between tiers of tubular heat exchangers. In process of exploitation of dam its stress state is controlled by heating of its downstream face in cold season. Heating is carried out by supply of water with temperature exceeding average temperature of free air of given locality for many years by preset value over pipe-lines arranged in tiers with the help of tubular heat exchangers. Water is supplied into tubular heat exchangers by circuit ensuring its flow in tubular heat exchangers in direction from downstream face of dam to its internal part and predominantly prior to rise of water in front of dam to level capable of causing tensile stress by upstream face of dam in absence of heating. Temperature condition of concrete dam is controlled by means of gear that includes flat coil pipe encased in concrete block which long elements are laid in parallel to downstream face of dam and which short elements are interconnected. Gear is fitted with three valves mounted on coil pipe, on additional tubular element and on long element so that heat transfer agent circulates over entire coil pipe in one direction except additional long element and in opposite direction over one part of coil pipe only which borders on downstream face of dam, additional long element included. EFFECT: enhanced operational reliability of concrete dams owing to creation of optimal temperature conditions in them. 7 cl, 3 dwg |
