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1.
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   

2.
1.  Sludge storage ponds can be located on any foundation soils, but economic calculations should be made for selecting the site.
2.  In the presence of seismic conditions, it is necessary to remove weak soils within the shoulder in order to provide its stability with a steepness of the downstream slope up to m=5. Other methods providing stability of the shoulder can also be used with appropriate technical and economic substantiation.
3.  The stability and possible liquefaction of soils of the shoulder should be determined only according to the guide Consideration of seismic loads when designing hydraulic structures, which is the only standard with respect to this problem.
4.  The size of the hydraulic-fill beach is determined on the basis of the particle-size distribution of the slurry.
5.  The permissible minimum width of the hydraulic-fill beach is determined on the basis of calculating the stability of the shoulder.
6.  It is necessary to recommend the construction of a siphon intake (discharge) located on the bank of the settling pool, which gives a more reliable and economical solution.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 12, pp. 53–55, December, 1991.  相似文献   

3.
1.  Investigations showed that when constructing dams of fine-grained silty soils by hydraulic filling, it is expedient to use the technology of layerwise placement of soil with consolidation of each layer.
2.  Dependences are given for calculating the thickness of the layers and period of consolidation of the soil on the basis of investigations of the dynamics of the hydrophysical properties of these soils in relation to technological factors.
3.  Dependences are also proposed for predicting the density of the hydraulic-filled soil during construction, as well as the distribution of soil in the profile of the structure.
4.  A method is proposed for calculating the technological parameters, in particular, the rate of construction of hydraulic-fill structures, calculating the size and number of the hydraulic-fill plots referred to one dredge, and prediction of the seepage discharge into the foundation of the dams during their hydraulic filling.
5.  The proposed calculation methods make possible a more substantiated approach to the design of hydraulic-fill structures of fine-grained silty soils and technology of their construction.
Translated from Gidrotekhicheskoe Stroitel'stvo, No. 6, pp. 5–9, June, 1990.  相似文献   

4.
Conclusions  
1.  The construction of dumps for toxic industrial wastes under complex geologic-industrial engineering conditions requires the development of special designs of anti-filtration screens ensuring the ecological safety of ground and surface waters in cases where significant deformations develop in the foundation bed of the structure.
2.  Under these conditions, the dumps should be designed and built with combined slightly permeable screens, the designs of which are determined on the basis of analysis of the chemical composition of the wastes stored in the dump, their volume, duration of service, and the geologic-engineering conditions at the construction site.
3.  Soil-film screens with polyethylene films 0.2–0.5 mm thick and rigid screen designs, to which concrete, concrete-film, and bituminous-concrete screens should be classed, are ineffective as experience with their multiyear service has demonstrated.
4.  Use of geomembranes no less than 1.5–2.5 mm thick, which are fabricated from dense polyethylene, compacted cohesive soils with a permeability of no more than 10-9 m/sec, artificial or natural solvents, and drainage layers in the structures of screens for dumps storing toxic industrial wastes should be a common rule for the design of these screens.
5.  The number of layers of anti-filtration and drainage elements, sorbing layers, and their thickness should be determined on the basis of special filtration and hydrochemical calculations performed with consideration given to the hydrogeological conditions of the disposal site, its capacity, and service life.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 13–17, February, 1999.  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.
1.  The adopted design and construction schemes for the dam made it possible to place, under complex geologic and hydrologic conditions, the dam fills without trench construction or drainage, which permitted starting sooner the fill placement work and sharply reduced the construction cost.
2.  For the dam engineering work, use was made of national and foreign experience in construction of high rock-earth dams -the dam core was constructed using clay-skeleton soil fills; the developed transition zones were made using fills consisting of inexpensive natural soils, which made it possible to eliminate the use of artificial mixes; and zoned placement of soils in the dam shells was carried out.
3.  The construction method and sequence made it possible to build the dam under complex climatic conditions within the established period and to use soils from useful excavations almost exclusively.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 6, pp. 12–16, June, 1991.  相似文献   

7.
1.  One of the new approaches to the use of wave power plants can be their use as a source of compressed air for operating a pneumatic breakwater.
2.  The use of wave power plants for protecting marine hydraulic structures from the effect of storm loads makes it possible to increase the cost effectiveness both of the WPPs themselves and of the hydraulic structures.
3.  A rough estimate of the cost of wave power plants shows their effectiveness as a source of electrical energy for remote regions of the USSR.
4.  The simplicity of the design of wave power plants enables organizing their mass production at shipyards or at the site of construction.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 7–10, February, 1992.  相似文献   

8.
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   

9.
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   

10.
Conclusions  
1.  The thermal stress-state of concrete masses being constructed on rock foundations with a complex relief can substantially differ from the corresponding state of masses having an almost flat contact with the rock foundation.
2.  The effect of the relief of the rock foundation on the stress-state of the block consists primarily:
in a change in the temperature distribution over the cross sections of the block, which determines internal restraint of individual parts of the block and restraint of the block in the foundation; in a change in the form of restraint of the mass as a whole in the rock foundation; in the formation of narrowed or expanded sections in the block, the stresses in which can substantially differ from adjacent ones; in the formation of stress raisers in the concrete for certain forms of the relief of the rock foundation due to jogs of the contact surface of the block and rock mass.
3.  The relief of the rock foundation can be the cause of occurrence of additional tensile stresses in the cooling concrete masses, leading to cracking in the concrete.
4.  The effect of the relief of the rock foundation on the solidity of the hardening concrete masses should be taken into account when constructing concrete hydraulic structures under harsh climatic conditions at stages of preparing the designs, drawing up technological regulations on performing concreting operations, developing and implementing programs of on-site observations with consideration of the particular climatic, geologic, production, and other construction conditions.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 15–18, July, 1998.  相似文献   

11.
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   

12.
1.  Small hydrostations under high-mountain conditions should operate with trash racks, devices should be provided for their cleaning from trash and shuga, as well as shuga-deflectors into the diversion canal.
2.  To reduce abrasion of the turbine equipment, it is necessary to provide operation of the suspended-particle settling basins.
3.  Specifications on the assembly of bearings and movable couplings should be developed for conducting maintenance works.
4.  During restoration works the profile of the runner blades should be made strictly according to the template in conformity with the plant drawings.
5.  Extremely necessary is the equipping of hydrostation with means for monitoring the technial parameters (bearing temperature, water pressure in the passage, wobble of the shafting, etc.), observation of the changes in which will make it possible to carry out in good time preventive maintenance and to reduce the probability of occurrence of breakdown.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 43–45, March, 1990.  相似文献   

13.
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   

14.
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   

15.
Conclusions  
1.  Theoretical investigations and bench tests on a pump model made it possible to obtain the setting geometry that ensures extremely good power characteristics for pumps having large setting flow areas.
2.  It is recommended to use wear-resistant white chromium-manganese cast iron for components in the setting of the GrT-4000/71 soil pump, which is intended for the transfer of sandy-gravelly soils with a lump size no greater than 60 mm.
3.  Use of a dual-cup rubber shaft seal is recommended to improve the operational reliability of the pump.
4.  To extend the longevity and improve the reliability of the drive of the soil pump, it is proposed to use a bearing with a set of spring that lower the axial forces on the bearing.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 31–37, February, 1999.  相似文献   

16.
1.  The most substantial and sharp changes in the state of the rock-concrete contact appeared beginning in 1985 after reaching 76% of the design hydrostatic load.
2.  Opening of the rock-concrete contact is distinguished by a nonuniform rate of change with time and nonuniform distribution of the amplitude of opening along the front of the dam, which reflects the complex interaction the dam with the foundation and effect of inhomogeneity of the foundation and different technological conditions of placing the contact concrete.
3.  Opening of the rock-concrete contact is accompanied by substantial changes in stresses and strains in the rock and concrete of the contact zone and in the piezometric heads in the foundation, reflecting structural changes in it during interaction of the dam with the foundation.
4.  In addition to the effect, which occurs for all types of concrete dams on a rock foundation, of technological factors and design differences of individual parts of the dam on the behavior of the contact zone of the foundation and concrete of the Sayano-Shushenskoe dam, also noted are such features as active opening of the rock-concrete contact over the entire length of the channel part of the foundation, presence of signs of hanging of the arch on the first columns on the banks, and a special stress state of the concrete in the lower part of the upstream face, which can be a reflection of the design features of the gravity-arch dam.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 10, pp. 44–49, October, 1991.  相似文献   

17.
1.  An on-site examination of the damageability of polymer-film skins and measurements of the seepage leakage made it possible to estimate the apparent permeability coefficient of such skins with relatively small damageability P<=0.05% by=" the=" quantity=">–3, m/day.
2.  Maximum damageability of polymer-film skins is formed due to the use of machines — bulldozers leveling the soil of the protective layer and vehicles delivering these soils.
3.  Introduction of mechanisms making it possible to place the protective layer of soil on the film element without traveling on the skin makes it possible to substantially reduce the damageability of polymer-film skins and their permeability.
4.  A reduction of damageability and permeability of polymer-film skins can be achieved by improving its construction and, in particular, by introducing bituminous and geotextile pads covering the film element of the skin on top and below, introduction of a second layer of film covering, and also by providing a drainage system of the protective layer.
Deceased.  相似文献   

18.
1.  Modeling of the processes of the interaction between outlet works and their foundation during passage of a flow by means of a model of the structure isolated from the channel, the flexibility index of which is less than unity, should be considered most correct, making it possible to completely reveal the mechanism of the effect of the flow on the structure and the reaction of the model of the foundation.
2.  Construction of the model as a primary detector made it possible to determine the main force parameters of the effect of the hydraulic jump on the basin and the frequency characteristics of the process of interaction of the basin and foundation.
3.  The character of oscillations of the basin model depends only on the method of supporting the model on the elastic foundation, and therefore for important structures it is necessary to model the base by trial and error.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 24–26, July, 1991.  相似文献   

19.
1.  The hydraulic projects awarded prizes by the Council of Ministers of the USSR in 1976 solve a set of critical national-economic problems and are distinguished by high cost effectiveness.
2.  Structures distinguished by originality and progressiveness of technical solutions, which ensure their reliable operation, have been constructed as the result of a set of scientific-research and design studies. This was made possible only by the close creative understanding and interaction between the scientific-research, planning, construction, and operating organizations.
3.  In building hydraulic structures, all the more attention is focused on industrial aesthetics. The architectural-planning solutions of the prizewinning projects are new, represent examples of the progressive development of industrial architecture, and have obtained widespread public recognition.
4.  The bold and economic solutions relative to the organization of the passage of flood waters over incomplete structures merit attention; this makes it possible to reduce the volumes of the enclosing foundation pits of the cofferdams, or eliminate them entirely.
5.  The experience gained with the design and construction of the prizewinning projects should be studied in detail and publicized for purposes of utilization in subsequent design and construction.
  相似文献   

20.
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   

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