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1.
Model studies of the hydraulic operating conditions of an eddy tunnel outlet with an inclined shaft showed that:
–  for regimes without delivery of air into the flow core with swirler parameterA=1.1 and with delivery of air for all values ofA, submergence of the outlet section of the conduit in the lower pool noticeably affects the size of the core and promotes the formation of a hydraulic jump zone along the tunnel;
–  insignificant (in value) submergences of the exit section of the tunnel have little effect on the discharge capacity of the outlet (their differences is Δ=1.4% forA=0.6, Δ=2.71% forA=1.1, and submergence even increases the discharge of the outlet Δ=0.8% forA=0.83).
–  delivery of air into the flow core has little effect on the discharge capacity of the structure, with the exception of the layout with a swirler withA=0.6 (Δ=4.31% forA=0.6, Δ=0.5%, and Δ=0.9% forA=1.1);
–  considerable vacuums are observed for regimes without air in the flow core, the absolute values of which with increase ofA drop intensely from Hfc=−4.5 m to Hfc=−0.3m;
–  delivery of air into the flow core markedly reduces the vacuums in it and their values are close to zero;
–  with increase of swirler parameterA the area occupied by the flow at the end of the tunnel decreases;
–  regimes without delivery of air into the flow core are the most favorable with respect to the conditions of the pressure distribution on the conduit walls;
–  submergence on the downstream side does not lead to an increase of pressure on the conduit walls if the vacuum in the flow core increases simultaneously with this.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 41–44, November, 1997.  相似文献   

2.
Thus, taking the following measures can be recommended for effective solution of the problem of preventing fouling of generator parts with oil:
1.  The enlistment of skilled specialists for evaluating the design of the installed seals from the viewpoint of current information about the distribution of air streams in the generator.
2.  Inspection of the seals of oil baths, determination of the places of leaks through existing loose fits, bolts, flange connections, etc.
3.  Conduction of tests for determining maximum vacuum zones and for a comparative analysis of pressures in and outside an oil bath.
4.  The development of an active protection system with withdrawal of oil vapors into the maximum vacuum zone to prevent steaming.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 22–26, August, 1995.  相似文献   

3.
1.  For locks with a head not exceeding 1.5 of the initial depth in the chamber it is most expedient to use the simplest supply systems of the lock-head type with filling from under the gate.
2.  For heads exceeding the initial depth in the chamber by more than 1.5 times, prevention of the entrainment of air by the flow filling the chamber should be provided. Preference should be given to the scheme with bypass submerged culverts in the upstream head, eliminating air entrainment.
3.  An analysis of the laboratory and onsite data shows that complication of the culvert supply systems from a certain level is not paid back by an acceleration of ship passage and improvement of ship mooring. Thus, for locks with a head on the chamber up to 40 m it is recommended to use a scheme with not more than four outlet sections (schemes 4 and 6 in Fig. 5). The ship mooring conditions for such schemes practically do not limit the chamber filling speed.
4.  An additional supply system can be used for accelerating the filling of high-head locks. The regime of the combined operation of main and additional supply systems is selected by model investigations.
Translated fromGidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 38–41, February, 1989.  相似文献   

4.
1.  The use of the scheme of a tunnel spillway with dissipation of energy inside the conduit in a shaft stilling basin under conditions of the Kambarata No. 1 hydrostation makes it possible to reduce the volume of earthworks and concrete in comparison with alternative variants and to protect the downstream stretch of the river valley from collapse of the slopes and substantial erosion of the channel.
2.  Investigations confirm the efficiency, reliability, and safety of the spillway and all its components.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 13–16, September, 1989.  相似文献   

5.
Conclusions  
1.  The developed method of strengthening lock chamber walls based on the use of prestressed beam members was substantiated by comprehensive calculations.
2.  The proposed method was realized successfully during strengthening and repair of the chamber walls of lock No. 1 of the Moscow Canal (sections No. 1–15).
3.  On-site observations of the behavior of the structures after their strengthening showed a substantial decrease of seasonal displacements of the lock walls and cessation of slipping of fragments of the walls into the chamber.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 17–21, April, 1999.  相似文献   

6.
Conclusions  
1.  The design of the steel-reinforced concrete pressure conduit was checked for four calculated cross sections: I-I, II-II, III-III, and IV-IV. The calculated check was made in accordance with Russian standards by analytical and numerical methods. The usual load combination of the operating period was taken as the main variant.
2.  The calculations showed that the strength condition of the conduit is fulfilled; in this case there is a considerable safety factor with respect to the shell and reinforcement, which attests to the degree of reliability and safety.
3.  Calculations of stresses in the steel shell and reinforcement by the FEM were made on the bases of finite-element models of cross sections with consideration of the formation of cracks in them. The calculated stresses do not exceed the strength of the steel shell and reinforcement.
4.  Conduit cross sections under temperature effects were calculated. Annual variations of the temperatures of the air, water, concrete of the dam, etc., were taken as the loads. The calculations showed that thermal stresses in the steel shell and reinforcement increase by not more than 24 MPa.
5.  A check of the design of the steel-reinforced concrete conduit showed complete fulfillment of the strength condition and high reliability of the design. The design of the steel-reinforced concrete conduits is recommended for realization when constructing structure of the Three Gorges hydro development.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp, 40–45, April, 1999.  相似文献   

7.
1.  The actual state of the outlet works as a whole can be evaluated as positive.
2.  To provide complete readiness of the outlet works for service regimes and to keep them in good working order, it is necessary to seal the existing damages and subsequently to carry out annual scheduled preventive maintenance.
3.  Long service of the restored bottom revetment of the stilling basin is possible under conditions of a moderate regime of waste discharges with their uniform distribution over the basin width, shortening of their duration, and reduction of the number of outlets put into operation.
4.  The restored basin revetment is in need of careful observation of its condition and sealing.
5.  The use of outlets for reducing the rate of filling the reservoir and especially for providing navigation releases is not permissible. They should be used only if the discharge capacity of the hydrostation units is insufficient for preventing filling of the reservoir during the spring flood above the elevation of the NPL as well as for not exceeding the NPL during passage of the summer-fall freshets with the reservoir filled to the NPL.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 9–12, April, 1994.  相似文献   

8.
1.  The real deformation of elastic chambers of the thrust bearing on a hydraulic support under a load is plane-inclined in certain cases.
2.  Adjustment of the load on the bearing segments with installation of one indicator on the chamber does not always provide the necessary accuracy.
3.  It is advisable to adjust the bearing according to the method presented with the installation of two indicators on the chamber, which provides the necessary accuracy of distributing the load between segments.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 30–32, May, 1995.  相似文献   

9.
Conclusions  
1.  The off-design operating regime of the Chirkey hydrostation with difficulties in producing electricity and with long periods of high upper pool levels under conditions of seismic activity negatively affects the reliability of the surrounding rock mass and should be brought into correspondence with the design.
2.  Long and nonuniform operation of the Chirkey hydrostation outlet in 1997 showed sufficient reliability and efficiency of the structures, but activated negative processes in the surrounding rocks masses. The rupture of two rock bolts supporting the unstable mass on the left bank and increase of the rate of settlement of the left wall of the canyon are a warning signal. This requires a thorough examination of all support members and development of outlet operating rules.
3.  The consequences of the operation of the outlet for the reliability and stress-strain state of the dam sould be specially and comprehensively studied and analyzed. It is urgently required to determine the forces in the rock bolts supporting the unstable mass, to determine the magnitude and places of maximum stresses in the dam, and to monitor the rate of movement of the left-bank slope.
4.  It is urgently necessary to organize appropriate seismometric monitoring on the dam and to obtain daily (weekly) bulletins of the Dubka seismic station and periodic reports of the OMP DNTs on the seismological situation in the region.
5.  Before organizing seismometric monitoring on the dam or geodynamic test area of the Center of the Geodynamic Observation Service in the Electric Power Industry, it is necessary to use the earthquake prediction method of the Joint Institute of Physics of the Earth with the help of the dam's existing measuring systems. For this purpose it is advisable to automate the reversed plump lines by the “Sibgeoinform” or DIGéS (Diagnosis of Hydraulic, Power, and Other Essential Structures) method and to increase the accuracy and frequency of seepage observation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 6–10, July, 1998.  相似文献   

10.
1.  The prefabricated cutoff wall as one of the economically justified designs can be regarded as the main watertight element of an earth dam.
2.  The cutoff wall can be made from precast asphaltic concrete and concrete blocks and combined — from both joined together on asphalt mastic. An analysis of the stress-strain state showed that each of these walls has a sufficient margin of deformability.
3.  The cutoff wall of precast concrete blocks, eliminating the use of asphalt for its construction and having a practically unlimited margin of deformability, can be of interest to designers and builders.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 11–14, November, 1993.  相似文献   

11.
1.  Provision for stability of slopes is one of the main problems in designing plains PSHS.
2.  The reasons for occurrence and a chain reaction of development of landslide phenomena on the south slope of the area of basic structures of the Zagorsk PSHS were peculiarities of its engineering-geological structure that were not properly taken into account in designing and carrying out construction work.
3.  For the purpose of stabilizing the landslide slope, a system of engineering measures was developed and implemented, including a change in the configuration and structure of the right-bank abutment of the upper-basin levee to the water intake, construction of a banquette, filling of a counterbanquette, draining of moraine loams, grading of the slope, surface water diversion, and monitoring of the state of the slope and elements of the antilandslide protection.
4.  Data from full-scale observatins indicate the effectiveness of the antilandslide measures that were performed and a state of the slope corresponding to criteria for the hydro development's safe operation.
5.  Innovative elements of the system of measures to stabilize the south landslide slope of the Zagorsk PSHS are:
–  the complex nature of measures, providing for the optimum set of criteria with respect to reliability, technological efficiency, construction time, and cost of adjusted expenditures;
–  minimization of one-time and total excavation for the banquette, providing for the least disruption of the slope in the process of construction;
–  draining of moraine loams, which has no known analog;
–  the use of an ejector unwatering system, which provides for minimum adjusted expenditures on construction and operation of the drainage system.
Deceased.  相似文献   

12.
1.  The problem of energy dissipation of the flow remains one of the most important in constructing high-head hydraulic structures with pulsating loads.
2.  During operation of the world's largest gravity-arch dam of the Sayano-Shushenskoe hydrostation, the energy of the flow being discharged is dissipated by a stilling basin. It was established that the powerful dynamic impulses created in this case originate, among others, from the baffle platform and its foundation. The latter circumstance requires the provision of reliable tightness of the joints between the blocks composing the platform and deep solid transition of the platform with its foundation.
3.  For the first time in domestic hydrotechnical practice fastening of the platform of the stilling basin by means of advance grouting and prestressed anchors installed to a depth greater than 20 m was mastered on the construction of the Sayano-Shushenskoe dam.
4.  Works on the manufacture, transport, assembly, tensioning, and testing PSAs were successfully mastered by the Krasnoyarsk enterprise of Gidrospetsstroi. A number of innovations were introduced at the know-how level.
5.  Passage of the 1992 floodwaters at the elevation of the NPL, after pumping water from the stilling basin, showed the effectiveness of the repair and restoration measures taken, which indicates the correctness of the selected designs, optimal technology, and high quality of the works of Gidrospetsstroi.
6.  An analysis of the strengthening works for high-head structures under analogous conditions permits recommending the following measures for designing and constructing a stilling basin: grouting of the foundation in the region of the stilling basin to a depth of 30–40 m;  相似文献   

13.
1.  Modified wood is an effective substitute of the laminated wood lining of bearing bushings for vertical pump units.
2.  An investigation of modified wood showed that this material in some indices (friction coefficient and wear resistance) is better than laminated wood.
3.  Since there is no mass manufacture and centralized supply of modified wood, it is possible to create a technological department for its production.
4.  Organization of the department does not require capital expenditures and special accommodations.
5.  Machining of the wood is performed on ordinary metal-cutting machines with the use of the tools used when machining laminated woods.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 33–35, July, 1991.  相似文献   

14.
Conclusions  
1.  Gidrospetsproekt should design the groundwater system.
2.  One contractor should drill the wells and operate the groundwater-lowering system.
3.  In connection with the geological conditions, the wells should be of very high quality, for which own enrichment of the filter material (sand of the blanket) and strict control during drilling the wells are necessary.
4.  It is efficient to drill the wells by a 1BA-15V rig with a tool with backwashing.
5.  With respect to piles of the penstock foundation: Drilling the holes for the piles should be done only with casings. To organize 24-h work for increasing productivity. Works on forming the pile heads should be done immediately after concreting the pile. The piles should be tested after each change in the geological conditions.
6.  With respect vertical drainage: the wells should be of high quality, with an enormous safety margin.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 29–33, October, 1999.  相似文献   

15.
Conclusions  
1.  The problem of prompt prediction of earthquakes can be solved by means of the measuring systems of high dams, provided a retrospective analysis of the response of these systems to seismic events that occurred and automation of the measuring equipment.
2.  After identifying the precursors and drawing up a forecast of the expected event in time, constant communication with the nearest seismic stations is needed for refining the forecast in a real-time mode.
3.  The standards of the USSR Ministry of Power and Electrification based on on-site observations for the stress-strain state of dams in seismic regions presently in effect should be changed with consideration of the need to monitor geodynamic processes and predict earthquakes in the regions of the dams.
4.  Before organizing geodynamic test areas at hydrodevelopments it is urgently necessary, on the basis of existing monitoring and measuring equipment and on-site observation services, to develop methods of practical prompt prediction of dangerous geodynamic processes on the basis of the proposed method [5,6] and to establish a close tie with the Dubki seismic station and OMP DNTs.
5.  In the shortest possible time with the help of scientists of the OIFZ it is necessary to work out scenarios of potential hazardous situations during tremors of various intensities and creep and landslide movements and measures to prevent possible damages and to perfect the prompt action of duty personnel under conditions of a seismic warning.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, pp. 42–46, September, 1997.  相似文献   

16.
1.  The energy-storage hydroelectric station (ESHES) can provide a 1.5–2-fold increase in peak capacity with a simultaneous threefold decrease in daily fluctuations of the water level in the lower pool.
2.  A decrease in the length of the concrete structures located in the river channel (especially the length) of the powerhouse) reduces the consumption of concrete for the ESHES in comparison with the HES, which compensates for the cost of constructing the additional structures of the ESHES.
3.  Unlike the HES, the ESHES operates in a sharp-peak regime and also during passage of flood waters.
4.  Contrarotating pump-turbines are best suited for an ESHES because of various combinations of heads on its turbine and pump parts.
5.  With increase in the speed of multistage hydraulic machines their placement depth decreases and the cost of the powerhouse is reduced.
  相似文献   

17.
1.  The movement of slurry during suction occurs through the center of the suction tip in the form of a vortex; moreover, the velocity of the vortex depends on the vacuum, and the cross-sectional area of the tip.
2.  Vigorous suction of soil (slurry) takes place when the suction tip comes in contact with the surface of the soil or with the tip embedded into the stratum of soil.
3.  With other suction conditions equal, the bulk consistency of the slurry remains the same for different tips to which the suction tip is embedded in the soil stratum.
4.  The minimum suction velocity depends on the fineness of the soil. The coarser the soil, the higher the suction velocity required. The minimum suction velocity of soil is defined by the relationship
  相似文献   

18.
1.  The substantial characteristic of the flow regime in an antiwhirl dissipator (AWD) is the presence in it of a region of significant dimensions, the pressure in which reaches the limit of the physically possible vacuum under these conditions, that is, the vaporization pressure.
2.  Supply of air in the quantity required for elimination under these conditions of the risk of development of cavitation (taking into account the pressure pulsations) substantially reduces the effectiveness of the AWD as an energy dissipator.
3.  The air flow required for protection against intense cativation erosion of a series of AWD zones should be limited by the discharge capacity of the air-feed system, characterized by the value μw=1.2 m2. In this case the averaged pressure drop in the air conduit may reach 6–7 m of water column, which corresponds to a supersonic velocity (about 400 m/sec, that is, more than five times the value usually permitted for aeration shafts). Under such velocities gasodynamic effects are possible (compression jumps, decrease of the discharge capacity, strong sonic phenomena), which call for special investigations.  相似文献   

19.
An analysis of the experience in the Soviet Union and in foreign countries with conveyor transportation in the mining industry, as well as with use of conveyors in hydraulic construction shows that the introduction of conveyor transportation in the field of construction of embankment dams in this country, for delivery of earth-rock material from quarries, as well as for carrying raw materials to concentrating plants processing nonmetallic minerals, will make it possible.
1)  To reduce substantially the personnel nees.
2)  To lower significantly the transportation costs for delivery of earth-rock materials to construction sites and to concentrating plants processing nonmetallic mateirals (rubble, gravel, and sand);
3)  To reduce the need for trucks, by replacing them with conveyors;
4)  To increase the rate of delivery of earth-rock materials from quarries for dam, construction and, consequently, to reduce the times of completion.
5)  To reduce the volume of housing, cultural-welfare, and auxiliary-subsidiary construction in owing to the lower needs for personnel in conveyor transportation;
6)  To eliminate the need for constructing a large number of roads with rigid pavements for large-capacity dump trucks;
7)  To raise the technical level of the earth-rock work.
  相似文献   

20.
Conclusions  
1.  In the upper reservoir of the Zagorsk PSS there are standing waves of a complex frequency spectrum having a virtually undamped character.
2.  The excess of the level of the crest of the upper reservoir embankment of the PSS should be selected with consideration of not only waves caused by meteorological factors but also the presence of standing waves.
3.  The standard systems of measuring the upper pool level of the PSS should provide for averaging the measurements.
4.  To eliminate nonproductive water losses through leaks of the close gate apparatus of the PSS units and increased power losses in the SC regime, it is advisable to provide for the installation of preturbine gates at newly planned PSSs.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 39–42, October, 1999.  相似文献   

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