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1.
1.  The developed dynamic model of the oxygen regime of the reservoir is in essence the next modification of the classical steady-state Streeter-Phelps model proposed for describing the interaction between dissolved oxygen and BOD on the river stretch.
2.  Underlying the given modification is the use, in the Streeter-Phelps model, of a dynamic ideal mixer model for describing the process of movement of water in the reservoir, unlike a river stretch, on a steady-state ideal displacement model and consideration of certain additional oxygen sources and sinks having a determining effect on the oxygen regime of the reservoir and related mainly to the production and destruction (mineralization) of phytoplankton as well as to the inflow of river and wastewaters and oxygen consumption by bottom deposits.
3.  The proposed dynamic model includes the main (numerical) and simplified (analytical) methods of calculating the oxygen regime of a reservoir, the practical use of which for calculating and predicting this regime in particular operating and planned reservoirs showed that they give similar results and, consequently, can be used jointly or independently of one another.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 19–25, July, 1996.  相似文献   

2.
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   

3.
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   

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.
1.  Intense passage of the sediment deposits washed from the upstream stretches of the reservoir through the cut was observed. In the cut itself or in the immediate vicinity of its outlet, 13,000 m3 of sediments was deposited, the remainder was discharged by the through-flow into the downstream pool.
2.  The cut made was not curvilinear in plan as was intended, and therefore its expected intensive erosion by the flow did not occur. The exception was the inlet stretch of the cut, where its erosion and widening by about 10 m occurred.
3.  An increase of the cross-sectional area of the reservoir due to the cut leads to some decrease of the level of the flushing flow in the main channel and increases its slope on the upstream stretch of the reservoir, increasing the flow velocity and effectiveness of erosion of the sediments. Furthermore, the directions of the flow velocities partially changed in the region of the cut, which intensified the effect of erosion of the sediments.
4.  Gradual erosion of the island of sediment deposits cut off by the cut from the left-bank mass of sediments was observed during flushing and subsequent operation of the reservoir.
5.  It is better to use diesel dredges for making cuts, which, with their self-contained power supply makes it possible to operate on any stretch of the reservoir at a sufficient distance from the bank.
6.  The cost effectiveness of combined removal of sediments can be estimated by comparing the cost of conducting it with the cost of removing sediments by hydraulicking as the cheapest of the presently known methods. For conditions of the Chiryurt reservoir the effectiveness was 0.9 ruble/m3 of sediments being removed for the particular flushing under consideration.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 34–37, August, 1989.  相似文献   

6.
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   

7.
1.  For design of the antifiltration components in the karstic rock, the entire potentially karstic mass was usually closed off with curtains.
2.  The constructed complex of antifiltration components, consisting of a grout curtain, concrete-filled karst hollows, and local concrete crosscut walls corresponds to the difficult geologic conditions of the Chain-N'yan massif.
3.  The adopted work organization, with construction of tunnels cutting across the entire karst mass, simultaneous rock grouting, and more precise determination of the geomorphology made it possible to considerably reduce the proposed volumes and costs of the antifiltration components of the Hoabinh hydraulic development.
4.  The adopted scheme for providing a working face for the antifiltration measures at El. 133 m was the optimal. It opportunely permitted ensuring readiness of the high-head front for filling the reservoir to El. 112 m in November 1990, and to the NPL at El. 125 m in September 1991.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 6, pp. 29–35, June, 1991.  相似文献   

8.
Conclusions  
1.  The mechanical effect of a reservoir extends to a rock mass whose volume exceeds the reservoir volume by two orders. This effect is expressed in the formation of a depression zone in the territory adjacent to the reservoir, “breakdown” of the reservoir walls, and extreme increase of the number of local earthquakes whose hypocenters are located within the indicated volume of the mass. Maximum changes in the stress—strain state of the mass occur at the reservoir filling stage.
2.  Stabilization of the reservoir levels causes stress relaxation in the mass within (0.8–-1.9)·108 sec, as a result of which static equilibrium of the mass—reservoir system is reached. Subsequently, surface deformations and stresses in the mass change in accordance with fluctuations of the reservoir water level. The number of local earthquakes decreases relative to the natural level. The intensity of “breakdown” of the walls decreases with rise of the water table.
A substantial change in the design operating regime of the reservoir causes significant changes in the stress—strain state of the mass, which are expressed in an extreme increase of the water table and drainage discharges in the dam foundation, increase of the number of local earthquakes, etc.
3.  Disturbance of the cause-and-effect relations in the reservoir—mass system can be regarded as a sign of a change in the regional stress field, including as a precursor of regional earthquakes.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 42–48, July, 1998.  相似文献   

9.
1.  The operating regime of the MFPT has a determining effect on the value and direction of action of radial forces.
2.  The presence of radial seals on runners does not lead to an unequivocal decrease of radial forces on the rotor.
3.  The use in MFPT of radial seals of the runner with the geometric parameters used in the usual turbines is accompanied by considerable RFs on the rotor, greater than in the turbines.
4.  A decrease of radial forces simultaneously in the PR and TR will cause difficulties in connection with differences in the values of the optimal parameters of the seals for each of the given regimes.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 12, pp. 22–25, December, 1994.  相似文献   

10.
Conclusions  
1.  Considering the urgent need to ensure a reliable year-round supply of electric power and process and drinking water to Khabarovsk, it is recommended to accelerate construction of the sediment/floating-anchor-ice/ice-protection shore bucket on the Amur River near the pumping plant for the Khabarovsk-3 thermal power plant with hooded intake heads with an overall productivity of 17,000 m3/h and 100% reserve.
2.  The study that we conducted is an example of the solution of complex problems, when specialists of various organizations are drawn upon to work as members of temporary creative teams. This is a reflection of the trend toward market relations in conducting scientific-research and experimental-construction work.
3.  Many of the solutions developed were first used in a complex; they may also be useful for other power plants or intake structures.
4.  The Khabarovskénergo and the profession as a whole should be interested in completing the construction of the designs that have been developed, since this will solve many problems of the supply of process and drinking water and make it possible to work out typical solutions for other projects with similar floating-anchor-ice/ice and channel complications.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 29–31, May, 1997.  相似文献   

11.
1.  During operation of large multipurpose reservoirs their unsatisfactory sanitary and engineering state, ineffective use of their water and biological resources, and unfavorable ecological conditions were revealed, which requires their immediate improvement.
2.  There are real ways of improving these sanitary state and use of the water and biological resources of reservoirs, which were established when drawing up the schemes.
3.  A thorough elaboration of ecological problems of the examined reservoirs aimed at an improvement of the ecological conditions on each reservoir and on the territories adjacent to them is required.
4.  To solve the stated problem it is necessary to implement a number of coordinated measures. For this purpose, a scientifically founded approach based on a prediction of the results of their accomplishment is required. The interrelatedness and interdetermination of these measures with respect to increasing the effectiveness of using water, land, and biological resources should be based on scientific approaches of aquatorial regionalization and planning of reservoirs. Such an approach, unfortunately, is absent in many schemes.
5.  The investments and expenditures being provided for the indicated purposes should be aimed at achieving priority goals on improving the sanitary state of reservoirs, water quality, and effective use of their resources. The investments provided for in the schemes should be based on real sources of financing and should be coordinated with the plan of the concerned organizations, which are the title holders of the objects planned for construction.
Deceased  相似文献   

12.
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   

13.
1.  With the creation of the Novosibirsk hydro development a water-management complex was formed on its basis, which unites water users and water consumers: hydropower, water transport, irrigation, municipal services, agriculture, forestry, fishery, etc.
2.  During the 30-year period of operation of the hydro development changes have occurred in the natural conditions on the stretch of the Ob River adjacent to the hydro development; the main one of them is deformation of the river channel in the lower pool of the hydrostation, which was the cause of the occurrence of a considerable shortage of water resources in years with a low runoff of the river.
3.  To increase the effectiveness of using water resources of the Novosibirsk reservoir, organizational and technical measures on providing the normal activities of the WMC under conditions of a shortage of water resources have partially been and will be carried out in the near future.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 18–22, January, 1988.  相似文献   

14.
Conclusions  Small rivers reflect to a considerable extent the general situation in the water-protection zone of the Ivankovo reservoir and make their negative contribution to worsening of water quality. Being the most vulnerable link of the ecosystem, they require some correction (if only from positions not requiring large material expenditures), namely:
–  banning plowing of lands up to the water’s edge and creating small forest strips in the near-channel part of rivers;
–  banning the application of fertilizer on snow in water-protection zones, since in this case a considerable amount of it enters directly into the rivers;
–  monitoring the observance by farm and poultry plant workers of the regime of sanitary zones of water objects, reference being to the impermissibility of the washout of wastes from the territories of these enterprises directly into rivers;
–  banning the grazing of large cattle herds on low and high floodplains, which owing to their territorial limitedness and instability to loads do not withstand such pressure and are brought out of an equilibrium state.
Assessment of the ecological state of small rivers and their drainage basins requires further development and refinement. But the preliminary results already permit concluding the need to reduce the level of anthropogenic loads on certain stretches of the basin right now and the need to legalize the status of sanitary zones for small rivers. To improve the water quality of small rivers of the drainage basin of the Ivankovo reservoir it is necessary first of all to elevate the ecological knowledgeability of the population living in the territory of the basin as well as to fulfill the scientifically founded standards of anthropogenic loads with respect to various types of use of resources. Furthermore, it is necessary to carry out water reclamation works on numerous stretches, which has not been done heretofore: clearing and deepening river channels and clogged springs; removal and utilization of trash and prohibiting the entry of wastewaters from the territories of agricultural and industrial enterprises directly into water objects (embanking the banks on hazardous stretches, creation of wastewater collectors, forest reclamation, etc.). Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 7, pp. 14–20, July, 1999.  相似文献   

15.
Conclusions  
1.  When designing pipelines on collapsing soils it is necessary to take into account the most unfavorable conditions from the viewpoint of bending of the pipeline—settlement of the intermediate supports every other one, all even or all odd.
2.  In this case, if the amount of deflection of the penstock under load is less than the amount of settlement of the intermediate supports, it is necessary to take into account disconnection of the intermediate roller support from work.
3.  Control assembly of members of the assembly links during manufacture of the oversize penstocks as well as quality control of the welded joints during enlargement are necessary conditions for achieving a high quality and eliminating losses of time during assembly.
4.  To shorten the time of construction and assembly works, provided a thoroughly conducted geodetic survey, it is expedient to assemble the penstock from two sides—from the side of the water intake and from the side of the powerhouse.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 40–45, January, 1997.  相似文献   

16.
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   

17.
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   

18.
1.  The rock foundation of the Sayano-Shushenskoe dam is inhomogeneous in its seepage characteristics: individual stretches in zones of tectonic crushing of the rock are the most permeable.
2.  The depth of opening of the rock-concrete contact does not exceed 27 m.
3.  During 4 years each subsequent filling of the reservoir to the NPL intensified the degree of decompression of the foundation, involving the deep curtain in this process. Signs of cracking of the middle part of the grout curtain were detected.
It is necessary in the very near future to take measures to suppress seepage through the rock foundation.  相似文献   

19.
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   

20.
1.  The level of meeting the water needs of the WMC participants (Pk) is not taken into account. Instead of this it is suggested to use a single value of the probability of meeting the water requirements of the WMC (PWMC). Then the value of the probability of meeting the water needs of the WMC participants Pk is taken equal to PWMC (Pk=PWMC).
2.  The parameters of the multipurpose hydro development are established on the basis of comparing the regime of the water source with the water consumption regime of the WMC during a long-term period. One proceeds from the condition that the parameters of each WMC participant is known.
3.  By means of the proposed method, the parameters of a multipurpose hydro development can be established in the entire range of variation of the probability of meeting the water requirements of the WMC. The zones of unregulated and regulated use of the river runoff and of excess and deficit periods can be established at the same time.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 28–30, July, 1991.  相似文献   

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