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1.
Conclusions  
1.  Clearing small silted rivers in the Volgograd and Rostov regions by means of floating dredges confirms the expediency of these works for irrigating farmlands, pisciculture, and improving ecology.
2.  Works on clearing and dredging small rivers have their own characteristics, which should be taken into account when working out the technical documents and performing the works.
3.  Simultaneously with channel clearing, comprehensive measures should be taken to prevent erosion of the banks and pollution of the river by wastewaters.
4.  The project documents should be drawn up with consideration of a multipurpose approach to the use of the river’s water resources.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 6, pp. 41–44, June, 1998.  相似文献   

2.
Conclusions  
1.  The expediency of hydraulic-fill grading of marshy coastal territories and city dumps for housing construction and recreation park and beach zones was proved practically.
2.  Underwater coastal borrow pits in the shallow-water zone can be used for direct dredging of soil.
3.  In the absence of sand borrow pits, fine-grained loamy sand soils can be used for hydraulic filling the construction sites.
4.  To operate dredges on large water areas under conditions of violent wind-wave action, it is necessary to work out a special works organization plan taking into account the preservation of supply lines, machines, and crew during a storm and under ice conditions in the winter.
5.  The possibility of using the ash of heat and power plants for engineering grading of a marshy territory for housing construction on a pile foundation was proved.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, pp. 29–33, September, 1997.  相似文献   

3.
1.  The designs as well as the total safety factor of concrete-encased steel pressure conduits of operating hydraulic structures were analyzed.
2.  The principles of the existing standards related to calculations of concrete-encased steel pressure conduits were analyzed.
3.  Methods of calculating concrete-encased steel pressure conduits (including forks and distributors), including elements of the inside steel shell and reinforced-concrete part, were developed.
4.  The calculation methods developed were experimental substantiated and tested during designing and constructing domestic and foreign objects.
Translated from Gidrotekhnicheskoe Stroitel'stvo No. 1, pp. 37–44, January, 1999  相似文献   

4.
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   

5.
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   

6.
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   

7.
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   

8.
1.  For the first time in Russia a submersible axial-flow dredge pump was developed and tested for installation as a first-stage pump on dredges to reduce the negative pressure before the hold dredge pump and to increase its positive suction head.
2.  The use of the axial-flow dredge pump permits increasing the output of the dredge and depth of excavating the underwater borrow pit. With respect to power consumption the axial-flow pipe is 2–3 times more economical than ejection.
3.  The small mass of the pump permits mounting it on existing dredges without their alteration.
4.  Development and perfection of this direction is quite prospective for hydraulicking.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 14–17, October, 1995.  相似文献   

9.
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   

10.
Conclusions  
1.  A set of measuring devices needed for operating a dredge was developed on the basis of domestic Sapfir-22 pressure transducers with protection of the pulse tubes by blowing or shutting in the air and was tested.
2.  A high reliability of the measuring set was found, it is recommended for wide use on dredges.
3.  The scheme of connecting the electrode detectors of the conductometric consistometer was improved, their series connection increases the accuracy of measurements by equalizing the electrode polarization process.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 7, pp. 28–30, July, 1999.  相似文献   

11.
Conclusions  
1.  When searching for the optimal steel percent needed for providing the bearing capacity of a specimen, it is necessary to take into account the factor of reinforcement arrangement in the soil.
2.  It is seen from the dependences γcd*=f(ζ) obtained for specimens with various steel percent that with an increase of the factor of reinforcement arrangement in soil ζ the work conditions factor decreases, which makes it possible to introduce the given factor in formula (1) for determining γcd*.
3.  The lining of the model must be regarded as an element increasing the bearing capacity of the reinforced earth model.
4.  In the case of a discontinuous and continuous lining the bearing capacity of the models (with the same steel percent) is higher than that of models with a flexible lining.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 3, pp. 19–21, March, 1998  相似文献   

12.
Conclusions  
1.  The systems of elongated triangles located at elevations 413, 467, and 344 m do not give reliable results, as a consequence of which they cannot be used as horizontal displacement meters.
2.  The displacements of the ends of the adits recorded from the NET readings are a consequence of measurement errors.
3.  The use of string systems as horizontal displacement meters of hydraulic structures can be used only with their complete protection from airflows, which is practically impossible to do.
4.  The use of 3-m invar bars, used as meters of the small sides of the NET, for determining deformations of concrete and bank adits is possible.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 52–54, September, 1998.  相似文献   

13.
Conclusions  
1.  It is necessary to calculate the strength of branches of penstocks by the finite-element method with the use of programs taking into account sufficiently completely the complex stress—strain state as well as the physical and mechanical properties of the material of the structure.
2.  When designing branches with large parameters it is expedient to use high-strength, sufficiently ductile, readily weldable steels with ultrasonic testing of the continuity of the rolled sheets.
3.  When calculating penstocks and branches concreted in mine workings it is necessary to examine their coaction with the surrounding concrete, and also it is recommended to take into account the unloading effect of the passive pressure of the surrounding rock mass.
4.  The loaded forks should be manufactured according to a special production plan of assembly and welding operations with the use of a technology providing a sufficiently low level of residual welding stresses.
5.  Check assembly and marking of the structural members during manufacture of bulky shaped elements of penstocks and forks as well as quality control of the welded joints during enlargement are necessary conditions of achieving a high quality of operating reliability which rule out losses of time when assembling the members.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 3, pp. 50–52, March, 1998.  相似文献   

14.
Conclusions  
1.  Pumped water storage of renewable energy sources is an effective method of coordinating the arrivals of renewable energy and consumer's load which are nonuniform in time.
2.  The use of water storage makes it possible to increase the firm output of power produced by plants based on RESs.
3.  The proposed characteristic makes it possible to optimize the production of plants operating on the basis of RESs and to minimize the volume of the water-storing system.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 12–15, November, 1998.  相似文献   

15.
Conclusions  
1.  Models constructed on the basis of network graphs to describe the operation of systems of construction machines can be used to derive simple analytical equations for determining the configurations and productivities of such systems.
2.  The concept of a master equipment is not always justified in defining the configuration of a system.
3.  In calculating the productivity of a system from the proposed equations, it is not necessary to introduce the shift time-utilization factor, because technological downtimes are automatically included in the operation of the system.
4.  The calculation of system productivity in matrix from can be implemented for both homogeneous and heterogeneous systems. The calculations can also be carried out for probabilistic systems, in which case computer engineering and pseudorandom-number generators are required.
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 2, pp. 24–28, February, 2000.  相似文献   

16.
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   

17.
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   

18.
1.  In certain cases of constructing dams salt-containing soils serve as their foundation.
2.  Under these conditions reliable operation of the structures can be provided only by developing special engineering measures to control dissolution.
3.  All existing methods of protecting saliferous foundation soils of hydraulic structures from dissolution can be divided into passive, active, and combined.
4.  The combined methods should be considered the most effective for preventing removal of salts from foundation soils by the seepage flow.
5.  Large-scale field investigations of the work of the combined method of protecting saliferous foundation soils of the planned Lower Kafirnigan hydro development showed its high effectiveness even in the case of complex engineering-geological conditions at the construction site.
6.  Individual elements of the set of dissolution protective measures investigated under field conditions can be used in hydrotechnical and hydropower construction practice.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 10–14, October, 1994.  相似文献   

19.
Conclusions  
1.  Russian hydropower engineering is a competitive branch of power engineering on the world market.
2.  The Russian Ministry of Fuel and Energy must create conditions for the formation and participation of domestic consortia in bids for turn-key delivery of equipment to Russian hydrostations, which will make it possible to reduce the cost, shorten construction time, improve quality, and ensure putting the units into operation on time, i.e., to use objective market mechanisms.
3.  On the initiative of the customer, certain conditions of storing, making up complete orders, delivery, and technology of installing equipment traditionally established between the customer and equipment suppliers should be revised by means of consortia for purposes of reducing costs and improving quality.
4.  One of the most important conditions for the successful work of the consortium is the clear-cut differentiation of responsibility between participants of the consortium.
5.  The date of synchronizing the unit should be taken as the date of reckoning the warranty period of the equipment.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 7–9, October, 1997.  相似文献   

20.
Conclusions  
1.  The vibration testing of hydroelectric units should be performed prior to and after overhaul.
2.  The volume of measurements taken during the tests should be sufficient not only for comparison of the vibration level with existing norms, but also for determination of basic impairments of the hydroelectric unit.
3.  It is expedient to include vibration tests with an expanded volume of measurements in the schedule for the overhaul of hydroelectric units.
Translated from Gidrotekhnicheskoe Stroitel'stvo. No. 12, pp. 21–22, December, 1997.  相似文献   

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