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1.
1.  The obtainment, as a result of numerous calculations on a computer, of generalized relations of the main indices of the load dropping process in the field TW/Tu–TW/TS makes it possible at the initial design stages to rapidly analyze the decisions made about the parameters of pressure conduits and pump-turbines and regulating regimes.
2.  By virtue of the peculiarities of the universal characteristics of reversible diagonal-flow pump-turbines, the maximum value of the temporal nonuniformity of the operation of the unit during load dropping in real ranges of the constants of inertia of the conduits and unit does not exceed the allowable standard value max=nmax/n0=1.6.
3.  The search for efficient regulating regimes reducing water hammer facilitates the introduction of the new concepts initial and final water hammer and plotting the corresponding zones on generalizing graphs.
4.  Rotating the runner blades of the diagonal-flow pump-turbines along with closing the gate apparatus after dropping the load is favorable for reducing water hammer. In this respect they can be more preferable than reversible mixed-flow pump-turbines for the same values of the heads, TW/TS and TW/Tu.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 23–27, January, 1991.  相似文献   

2.
1.  The results of the first full-scale experiments with orthogonal wind turbine generator units showed their performance, the possibility of creating on their basis large units of a simple design intended mainly for use in power systems.
2.  The maximum wind power coefficient of the rotorC n somewhat exceeds the calculated values, reaching values of 0.50–0.56 at blade speeds equal to about three wind speeds.
3.  The aerodynamic drag coefficients of structural elements of type VL-2 rotors with guys can reach a=0.06–0.07, which substantially exceeds the profile drag of the operating blades. Elimination of the guys and a relative increase of the area of the working blades in type VL-2N rotors makes it possible to reduce the indicated drag coefficient to a=0.031–0.033.
4.  At wind speeds exceeding 0.5–0.6 the blade speed and power output of the unit cease to depend on the wind speed. This property of orthogonal units protects the generator from overloads, simplifies regulation, and increases the reliability of the plants.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 49–53, November, 1988.  相似文献   

3.
1.  An intake structure with a closed flow having a vertical axis of rotation contributes to the development of a favorable kinematic structure in the channel, which makes it possible to minimize scouring beyond the structure.
2.  Excedence of the near-bottom average and maximum velocities above the average velocities in the channel comes about atl3.3hc downstream from the axis of the intake.
3.  The magnitude of the ratio of the maximum 1st-percentile and average 50th-percentile flow velocities (v1%/v50%), which characterizes the velocity pulsation, attains values for the undisturbed flow in the near-bottom region at a distancel4.1hc.
4.  Complete equalization of the plan diagram of velocities is noted at a distance (4.9–7.8)hc from the axis of the intake structure.
Translated from Gidrotechnicheskoe Stroitel'stvo, No. 4, pp. 17–19, April, 1991.  相似文献   

4.
1.  The accuracy of modeling the velocity field depends heavily on the orthogonality of the grid being generated. Deviation from orthogonality even by 10° increases the ductility of the scheme markedly.
2.  It is necessary to relate bottom erosion not only to the tangential stresses on the bottom, but also the distribution of the kinetic energy of turbulence along the bottom.
3.  In studying channel deformations, a diffusion model with a terminal velocity is most effective, among other things, because it does not include difficult-to-determine diffusion coefficients that enter into a semi-empirical model.
4.  It is better to establish the adhesion condition, and not the reflection condition on the bottom for descending particles — this perceptibly changes the velocity of the bottom forms and their transformation.
5.  A change of ±50% in the transfer frequencies ik that enter into the diffusion model has virtually no effect on the computed deformation of the bottom.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 42–45, November, 1990.  相似文献   

5.
1.  The stockholder firm Gidrospetsstroi first developed, made feasible, and completely mastered a new procedure for work involving the monolithizing of large-diameter steel-reinforced-concrete pipelines in the domestic practice of special operations. 978 butt joints between individual elements have been successfully grouted.
2.  A procedure for monolithizing joints between reinforced-concrete elements in pipelines, which has been implemented in the construction of the Zagorsk water storage power plant, can be classified as a new technically complex form of special hydrotechnical operations. In conducting the work, it is necessary to focus attention on strict observance of the work procedure and on the possibility of bulging of the metallic lining of the conduit in the case where injection requirements are not observed. The work requires attending personnel with high qualifications, and should be accompanied by careful certification inspection to guarantee reliable quality of the work.
3.  Operations involving the monolithizing of butt joints in the steel-reinforced-concrete pressure pipelines have important principal differences with respect to the classical grouting of joints in monolithizing concrete dams and with respect to work involving the grouting of massive reinforced-concrete blocks possessing elements of a work procedure involving filler grouting beyond the facing in individual cases.
4.  The firm Gidrospetsstroi, which has significant experience in the design, technology, production, and quality control of special operations, guarantees their successful execution. The firm offers highly qualified specialists, production equipment, the timely publication of design-estimate documentation, and the realization of careful control (in the form of certification inspection) over the quality of their work.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 11–15, August, 1992.  相似文献   

6.
1.  Despite their openness, transverse discontinuous structures have a jetty effect.
2.  Discontinuous structures formed by two rows of rectangular support masses connected by longitudinal beams have the strongest effect on the dynamics of a pebble beach.
3.  It can be recommended to use circular supports with a diameter of not more than 2 m arranged in one row at a distance of at least 6 m from one another for constructing hydraulic structures intersecting pebble beaches.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 23–25, May, 1989.  相似文献   

7.
1.  Processes of variation of the dam-foundation-abutments system are not fading away, the operating regime of the structure has not stabilized.
2.  The unsteady and inelastic work of the bank abutments, evidently, is one of the causes of irreversible radial movements and development of fracturing in the first column of the dam.
3.  Cracking on the upstream face and progressive seepage through the concrete of the first column worsen the state of the concrete and the cracks are subject to healing by polymer materials. Polymer injections do not improve the work of the structure, but if the cracks are not healed promptly the volume of necessary repair works will increase with the course of time.
4.  To evaluate the stress state of the dam it is necessary to make calculations with consideration of the large stress raisers: water intakes, gate grooves, etc.
5.  It is required to evaluate the fact of the excess by a factor of 2–3 of the increments of the maximum arch stress over the design values in various load ranges.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 21–25, April, 1994.  相似文献   

8.
1.  The morphometric method of estimating the geometry of stable canal channels, as based on a deeper physical nature and using the fluvial process theory principle, has become most popular in solving the problem of designing canals in alluvial soil. It can be considered that sufficiently reliable relations have presently been obtained which can be used in practice with consideration of the particular canal operating conditions.
2.  More detailed investigations of the separate consideration of the transport of bottom and suspended sediments on stability for providing channel stability of canals when vvne are needed for refining the morphometric relations.
3.  It is necessary to continue investigations of the effect of the sediment concentration of a flow on the velocity structure of the flow and noneroding velocity.
4.  It is necessary to consider as one of the most important problems of open-channel hydraulics the activation of experimental and theoretical investigations of the three-dimensional turbulent structure of a flow for the purpose of estimating the distributon of local velocities in the flow cross section as a function of the size of the channel and roughness of its walls.
5.  For dynamically stable canal channels investigations are needed for estimating the roughness coefficient as a function of the channel size , shape, sediment concentration of the flow, and bed-load transport.
6.  It is necessary to prepare the relevant materials for compiling standard data on the design of dynamically stable canals.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 37–42, March, 1991.  相似文献   

9.
1.  Records of earthquakes with an intensity of 3–5 recorded at the same observation point on a rock foundation near the Chirkey dam were examined. The data of the horizontal and vertical components of the seismic oscillations were analyzed. The seismometric data were processed by two methods — manually and according to the Spectrum program on a BÉSM-4 computer.
2.  For the accelerograms practically coinciding values of the maximum intensities of the seismic oscillations Amax with a period Tmax=0.18 sec were obtained for the horizontal and vertical components. For the velocigrams Amax=2.6 cm/sec with Tmax= 0.07 sec for the horizontal component and Amax= 3. A cm/sec with Tmax=0.07 sec for the vertical component.
3.  The spectra obtained with computer processing of the accelograms indicate that the maximum intensities of oscillations for the horizontal and vertical components lie in the same interval of frequencies 2<><=9 hz,=" but=" for=" the=" horizontal=" component=" the=" maximum=" at=" frequency=" 0.2=" hz=" is=" absent=" and=" the=" entire=" spectrum=" is=" somewhat=" shifted=" into=" the=" high-frequency=" region.=">
A. The machine spectra of the velocigrams for the horizontal component show maximum values in the interval 2<><=6 hz=" and=" for=" the=" vertical=" in=" the=" interval="><><=8>  相似文献   

10.
1.  The fluvial processes in the Ob River downstream of the hydro development, which markedly changed after damming the river and creation of the reservoir during the first decade of operation of the hydrostation, were expressed in the natural process of deep erosion of the channel, which had a diminishing character.
2.  Starting with the second half of the 1960s, quarrying in the Ob channel on the 30-km stretch of the lower pool adjacent to the hydrostation began to have a substantial effect on the natural process of transformation of the channel due to streamflow regulation and retention of sediments by the reservoir.
3.  During the period between 1966 and 1984 more than 40 million m3 of sand-gravel mixture was removed from the river channel and floodplain in the indicated stretch, as a result of which the decrease of levels relative to the normal, natural values at the site of the Novosibirsk gauging station was 0.9–1.0 m.
4.  A decrease of the levels downstream led to a deficit of water resources of the reservoir in dry years and, as a consequence, to worsening of the operating conditions of the majority of participants of the Novosibirsk water-management complex.
5.  After some stabilization of the position of the levels in the river in 1984–1986, the decrease, slump, of the levels in the stretch passing through the city subsequently resumed beginning in 1987–1988. The rating curve for the Novosibirsk gauging station in 1988 shifted downward from the analogous 1986 curve along the height axis by 15–20 cm.
6.  The priority task facing water users and consumers of Novosibirsk is the fastest possible realization of the recommendations of MGU, VNIIG, and ZapSibRNIGMI on partial restoration of the water levels in the stretch between the hydrostation and Novosibirsk city by constructing embankments damming nonnavigable branches and converting the Ob channel here at low-water discharges (less than 2000 cm3/sec) into a single-branch channel.
7.  For a radical solution of the problem of reliable provision of water consumers of Novosibirsk, it is necessary to reconstruct all intakes located downstream of the hydro development.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 25–28, October, 1989.  相似文献   

11.
1.  A microprocessor-based device was developed for checking (measuring) the level of the insulation resistance of the stator winding of a unit in the range 0.5–500 M and absorption coefficient in the range 1–10 with output of the measurement results to a digital indicator.
2.  All measurements are taken on a stopped or operating unit in a semiautomatic regime after pushing a button on the face panel of the device. It is possible to use the device as part of a process control system or in a diagnostic system with automatic control from a computer.
3.  The device underwent a check on the units of the Skhodnya and Chirkey hydrostations, where it showed good results. It is suggested that it be introduced.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 43–45, September, 1989.  相似文献   

12.
1.  The construction of facilities of the southern Yakut hydropower complex, making it possible to bring 23–25 billion kWh of renewable energy resource into the energy balance of the Far Eastern power region, should become one of the strategic directions of power construction.
2.  For further elaboration of the concept of development of the energy base of the Far East, it is necessary in the shortest possible time to work out a Feasibility study of the southern Yakut hydropower complex, in which problems of the organization of construction and social and commercial substantiation should be elaborated; in the latter it is necessary to investigate all possible variants of obtaining such large investments in construction.
3.  The creation of the SYaHPC in the territory of the Yakut ASSR will have great significance for the development of the economy and improvement of the living conditions of the population of the republic. Export of part of the electricity to China will make it possible to reliably and constantly meet (as compensation for the removal of lands) a considerable part of the republic's needs for vegetables and fruits and other goods; it will make it possible to eliminate investing a part of the means and material and labor resources in unproductive and unprofitable agricultural enterprises.
4.  The SYaHPC with partial export of the electricity being generated at its hydrostation, being practically unaffected by inflationary processes by virtue of low operating expenses, under market economy conditions in the future can become one of the most profitable enterprises, a most important object of international and regional economic collaboration in the RSFSR.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 52–56, February, 1991.  相似文献   

13.
1.  Despite the decisions made repeatedly at various conferences and seminars, there are still no scientific design guidelines. As a consequence of this, crucial decisions are made without sufficient substantiation and thorough evaluation of the decisions made.
2.  Research institutes should not be limited to collecting data on settlements and temperature and seepage regimes of dams, but on the basis of data already available should give clear-cut standards and regulations for the design of earth structures in the northern construction-climatic zone.
3.  The construction of transition zones between the rock fill of the downstream shoulder and foundation, drainage blanket, and relief drainage is mandatory in all cases when the foundation is composed of fractured rocks covered by a diverse stratum of loose soils of various origin.
4.  The core-filters-drainage system should be a zone of increased attention when performing works and assigning the characteristics of the soils being placed. As far as possible, it is necessary to change to dam designs with narrow cores protected by transition zones and developed drainage. When constructing such dams in the winter, especially in the case of heavy snow falls, it is easier to check the quality of placing the material in the zone of increased attention — core-filter.  相似文献   

14.
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   

15.
1.  An industrial procedure for electrofacing by a powder wire of special composition has been developed to produce a wear-resistant coating up to 5 mm thick on the components of suction dredges. An increase of 4–6 times is achieved in the time to failure of the faced components, while the cost of these operations does not exceed the price of the initial article.
2.  It is expedient to use the facing procedure to strengthen new components under plant conditions and to restore worn parts at the site where the suction dredges are operated. The Scientific-Production Spetsstal' can perform work on electrofacing with the required materials, equipment, and technical accompaniment, and organize the strengthening of components at the plant.
3.  The installation of a three-channel suction dredge with effective water protection of components from abrasive wear while eliminating overflow of slurry into the pump and increasing the efficiency of the unit on the whole is proposed. The proposal is recommended for development and implementation.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 10–13, March, 1995.  相似文献   

16.
1.  The unique arch dam of the Chirkey hydroelectric power plant is operating under difficult conditions of high natural and excited seismicity under a geodynamic load from the left bank, which is not well defined. Reliable design solutions and the safety factor of the concrete have permitted its reliable operation to date.
2.  The rock mass enclosing the dam exhibits appreciably lower reliability. The clay interlayers contained in the rock and the pattern of dislocation lower the shear strength under the influence of saturation, changes in the upper-pool level, and repeated earthquakes. The safety of the hydraulic facility is determined by the stability of the laft-bank/dam/right-bank system under left-bank creep caused by the gravitational imbalance of the site.
3.  To retain the proper level of reliability and safety of the Chirkey hydroelectric power plant, it is necessary to perform check geomechanical calculations and organize state-of-art monitoring of geodynamic processes and an earthquake-forecasting service.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 30–35, May, 1994.  相似文献   

17.
1.  Absorbing formwork has a substantial effect on concrete quality for concretes with W/C0.365.
2.  The concrete surface quality depends on the quality of the absorbing formwork materials used.
3.  The possible amount of water removed from the concrete by means of the absorbing (vacuum) formwork was 2.4–3.57 kg/m2.
4.  Before the start of hardening of the concrete, its water content decreases by 20–30% at a depth to 15 cm from the absorbing formwork. During hardening of concrete, its water content equalizes over the entire length of the specimen (thickness of the block), and under these conditions the W/C ratio of the concrete near the formwork is not more than 1% below the initial.
5.  According to the results of testing the concrete for cavitation resistance, the best indices were noted for formwork containing ensonite. In this case, the cavitation resistance of the concrete was increased up to 1.4 times. The latter circumstance permits recommending for use as formwork absorbing material fine-porous paperboard of the ensonite type (with pore sizes 20–100 Å), which freely passes water molecules but retains cement particles.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 39–41, November, 1989.  相似文献   

18.
1.  The installation of a conical transitional segment between a tower (shaft)-type water intake-outlet and penstock affects a significant reduction in head loss in the pump mode, but has virtually no effect on the magnitude of the latter in the pump mode.
2.  The existence of a conical transitional element in the pump mode appreciably lowers the discharge velocities of the flow and increases the effective height of the water-passing openings by 1.5–1.7 times when the height of the intake openings h0.5dp.
3.  The head losses in the intake-outlet decrease in the pump mode of operation with increasing degree of expansion of the transitional diffusor segment.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 21–23, November, 1992.  相似文献   

19.
1.  The design scheme of the 500-kV OEE of the Sayano-Shushenskoe hydrostation has a number of substantial shortcomings reducing the reliability of power output. Reconstruction of the middle network of the existing 4/3 scheme to three networks with two switches per connection is the most optimal variant of reconstruction. Sectioning of the collecting bus systems is necessary for a further increase of the reliability of the scheme.
2.  In the case of repair works on equipment of small nonstandard switchgear, such as the 500-kV OEE of the Sayano-Shushenskoe hydrostation, it is necessary to use special equipment and mechanisms, the development of which must be recommended to domestic industry.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 37–39, April, 1994.  相似文献   

20.
1.  Devices for measuring all dredge operating parameters were developed and tested.
2.  The devices developed are distinguished by simplicity of design, accessibility for manufacture in workshops, their installation and adjustment can be performed by the dredge crew according to the available instruments.
3.  The technical manuals can be sent by the authors by agreement with customers. For concluding an agreement, contact the article's coauthor N. N. Kozhevikov at the address: 105568, Moscow, Chechulin Street, house 22, apartment 22, telephone 308-80-96.
Methods MI 1948 -88can ordered from Hydrotech enterprise at the address: 103062, Moscow, Chaplygin Street, house 5.  相似文献   

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