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1.
1.  At present Gidroproekt has gained considerable experience in calculating the stability and designing rock slopes. In all, the stability of more than 100 slopes at 20 Soviet hydropower facilities has been analyzed during the period since 1970.
2.  Cases of failure of the masses related to errors in design have not been observed at a single one of the designed slopes, which permits concluding the soundness of the method used by the authors for calculating the stability of rock slopes and analyzing the initial information.
3.  The conditions of conducting and the parameters of drilling and blasting operations have a noticeable effect on slope stability and their angles, which indicates the need for the thorough development and rigorous observance of the plans of the drilling and blasting operations.
4.  At a number of hydropower facilities detailed calculations of stability made it possible to eliminate costly engineering measures, as a result of which about 1 million rubles were saved.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 12, pp. 4–8, December, 1989.  相似文献   

2.
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   

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.
1.  The development and mastering of the high-speed tiered method of constructing arch dams on the construction of the Miatla hydrostation provide a high rate of construction with observance of the design requirements imposed on the quality and reliability of the structures. Successful completion of the construction of the Chirkey and Miatla arch dams, their normal behavior under a load indicate the possibility of the wide use of this most economical class of retaining structures.
2.  It is expedient to examine the problem of increasing the quality of arch dams and expanding the geography of using this economical class of structures, considerably shortening the time of creating hydro developments with the use of tiered technology.
3.  Further investigations and developments should be aimed at creating quickly repairable concrete beneficiation facilities, highly mechanized systems as part of the cable cranes, conveyor systems, and means of intrablock mechanization providing a further increase in the rate of high-speed construction of arch dams.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 24–26, March, 1989.  相似文献   

5.
1.  Construction of dams by the flow-line technology provides a high rate of their construction with minimum labor expenditures.
2.  Construction of rock embankments from a rock mass by the method of compaction due to the kinetic energy of impact provides sufficiently reliable compaction of the fill.
3.  By such a method it is possible to construct embankments from strong rocks. Weak rocks at the time of impact will be broken, not providing reliable compaction of the fill.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 6, pp. 25–26, June, 1992.  相似文献   

6.
1.  When constructing earth dams the inclusion of foreign members in the form of reinforced-concrete galleries, shafts, etc., in the body of the structure is impermissible. It is also desirable to eliminate the construction of a grouting gallery under the dam. The foundation should be grouted either before or after constructing the dam.
2.  Installation of monitoring and measuring equipment for observations during operation must be done after completing construction of the dam. Installation of MME during construction leads to its complete disturbance, holds up the rate of filling, and affects the quality of the works.
It is impermissible to construct concrete galleries on made ground. Elements of the dam should be constructed on a homogeneous foundation.  相似文献   

7.
1.  Seasonal variations of the piezometric head in homogeneous earth dams, as a rule, are due to changes in the viscosity of the seeping water caused by temperature fluctuations.
2.  A further study of the interrelation between the temperature of the seeping water and parameters of the seepage flow is promising for increasing the reliability of evaluating the state of earth structures of hydro developments.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 25–27, September, 1988.  相似文献   

8.
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   

9.
1.  Rollcretes can meet the requirements of construction concrete with a high strength, impermeability, and frost rsistance and, in particular, can be used with great effectiveness for constructing hydraulic structures such as arch dams, retaining walls, abutments, etc. Furthermore, road pavements, landing strips, and taxiways can be constructed from them.
2.  With consideration of the relative cheapness of low-cement rollcrete, in a number of cases it is possible to replace reinforced-concrete members by pure concrete ones, keeping in mind the high cost of reinforcing steel.
3.  The technological characteristics of rollcrete enable doing away with framework at the concrete-ground contact, which is important when constructing transition structures.
4.  It remains to develop a technology of equally strong joining of layers of high-strength rollcrete, which will require a rather large volume of experimental works.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 8–10, July, 1992.  相似文献   

10.
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   

11.
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   

12.
1.  Geodynamic movements of surrounding rock masses can affect the behavior of arch dams. Creep movements of slopes can cause a change in the former scheme of static behavior of a dam, being expressed in a different reaction to the previous combination of acting loads.
2.  The effect of seismotectonic activity during the earthquake precursory period is manifested in the form of fluctuations of the on-site data: strain-gauge, geodetic, and piezometric. The location of the detector that recorded fluctuations and values of these fluctuations characterize the temporal change in the scheme of static behavior of the dam reacting to deformation of the blocks and slabs of the surrounding masses.
3.  For concrete dams constructed in narrow mountain canyons, it is necessary to conduct on-site observations according to a special program compiled on the basis of an analysis of the state of the dam in the first years of operation to detect geodynamic and seismotectonic activity. These observations should be informative for: Determination of the effect of the surrounding rock masses on the state of the dam; study of the role of technogenic factors in natural processes; selection of earthquake precursors; determination of the seismic stability of the dam.
4.  On all dams constructed in mountain canyons it is necessary to make a retrospective analysis of the on-site data to determine the interrelations in the reservoir-dam-surrounding rock mass system.
5.  The data of on-site observations of the responses of a dam to geodynamic and seismotectonic processes can be used by basic science for gaining knowledge about the earth's crust.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 20–23, July, 1993.  相似文献   

13.
Conclusions  
1.  In connection with the fact that potentially unstable masses exist in the immediate vicinity of the dam and powerhouse, which are referred to as Class I structures in terms of capital expenditures, the approach taken for the design of PUM stabilization should be nonstandard with consideration given to a number of permanent vibratory design loads introiduced by operating hydraulic units and spillways, as well cyclically varying loads due to the weight of the water in the reservoir and the weight of the structures.
2.  It is proposed to define the volumes required for PUM stabilization of the left-bank slope more precisely on the basis of observations of PUM during construction and operation of the hydroelectric plant. The interruptions that have occurred in the instrument observations should therefore be recognized as impermissible.
3.  Construction and operating experience has demonstrated that it is expedient to perform work on stabilization of potentially unstable masses prior to the start of construction on entities located in their immediate vicinity.
4.  A protective rock wall built at the foot of the slope cannot provide for the complete safety of the structures located close to the left-bank slope during the collapse of rock blocks or individual stones.
5.  On-going monitoring of the condition of the left-bank slope does not correspond completely to problems of providing for the safety of the structures and personnel at the hydroelectric plant by reason of the low reliability of the measuring equipment.
6.  Use of the automated “Relos-L” system for observations of the condition of the rock masses will make it possible to carry out continuous on-going monitoring within the framework of the automated production-control system at the Sayano-Shushenskoe hydroelectric plant. Only a multifunctional monitoring system, which includes different kinds of independent observations, can provide a sufficiently valid evaluation of the state of the PUM, and, on their basis, determine measures to prevent possible emergency situations.
7.  The collapse of PUM in the initial stage of construction with subsequent plaining of the slope and the organization of multistory rock-entrapping benches is a more reliable, safe, and, probably, economical (if expenditures for future operation are assumed in the calculation) method than their stabilization.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 67–71, September, 1998.  相似文献   

14.
Conclusions  
1.  It is necessary to revise urgently SNiP 2.06.05-84x with respect to the designs of dams being constructed in the northern construction-climatic zone, i.e., to remove all vagueness in understanding the basic design principles.
2.  The top of watertight zones of dams should exceed the elevation of the HFL by amounts specified by SNiP. When necessary, in connection with seasonal freezing and thawing of the upper part of the core, additional measures should be provided for ensuring local static stability and seepage strength.
3.  Large dams should be evaluated under the aegis of the National Committee on Large Dams, whose role in this matter must be increased. It is necessary to establish legislatively the procedure of changing the designs of dams after approving the projects.
4.  A coordination center processing all information on construction and operation should be created for large dams and dams being constructed in the northern construction-climatic zone. The best solutions should be recommended for implementation.
5.  It is necessary to reconstruct the upper part of the dams of the Kureika hydrodevelopment, using above the NPL soils of an analogous composition for the entire zone of the core with provision of its seepage strength by an additional filter layer of sorted sand of fractions 0–10 mm. Reconstruction of the dam crests will make it possible not only to obtain additional power production due to the prism of the reservoir between the NPL and HFL within 150–200 million kWh/yr.
Translated from Gidrotekhnicheskoe Stroitel’stvo. No. 3, pp. 41–45, March. 1998.  相似文献   

15.
1.  Consideration of the three-dimensional character of seepage flow in the region of shore abutments in rock-and-earth-fill dams exerts a major influence on the basic seepage parameters required for the design of the core profile, the gradation of soils in reciprocal filters of transitional layers, etc.
2.  The three-dimensional character of the flow exerts the most significant influence on the value of Jdis, especially along the line of contact between the lower face of the core and the shore slope Jdis.S. In that case, the steeper the slope, the greater amount the values of the discharge gradients are lowered.
3.  With three-dimensional seepage, increased Jdis values arise in the core primarily along the water line of the lower pool and the line of contact between the lower face and horizontal underflooded sections; it is precisely in this connection that special protection should be specified.
4.  In evaluating the seepage resistance of the core soil for contact overflow, it is recommended to use the component of the gradient Jdis normal to the plane of the downstream face Jn.n as the computed discharge pressure gradient.
5.  Computational relationships for determination of parameters of three-dimensional seepage, which are required for engineering calculations of the cores of rock-and-earth-fill dams are proposed in the paper. Computational methods based on plane seepage yield significant errors in a number of cases, and should therefore be used with certain caution, even in preliminary stages of design.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 7, pp. 24–29, July, 1993.  相似文献   

16.
Conclusions  
1.  A sliding transition makes it possible to transmit the entire horizontal pressure of the upper pool to the downstream shoulder of the fill dam. The use of a bitumen coating on fibreglass fabric as a sliding elements provides complete impermeability of the sliding joint.
2.  Deviation from a linear distribution of the passive earth pressure of the downstream shoulder on the vertical face of the diaphragm and facing remains unclear in a calculation respect, although room for these deviations is small. For a rigid facing these deviations do not have significance, for a diaphragm they can affects its design.
3.  The profile of a fill dam with a vertical concrete facing having a sliding transition shown in Fig. 1 is the results of the design studies. This profile can be recommended with confidence as the initial one for further designing. With respect to the design of the diaphragm, there is nothing concrete at present.
4.  It is desirable that design organizations whose designs of hydrostations have still not been approved prepare also alternative variants of dams with facings.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 53–54, November, 1999.  相似文献   

17.
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   

18.
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   

19.
1.  The proposed complex index (reduced relative roughness), characterizing the maximum degree of smoothness of the surface of the working with appropriate energy expenditures on its formation, meets the requirements of the technological criterion of optimality of smooth-wall blasting parameters.
2.  The optimal value of the burden-to-charge spacing ratio is determined only by the relationship between the diameters of the blasthole and of the charge located in it. The absolute values of the parameters of the arrangement of the blastholes should be determined on the basis of the established optimal burden-to-charge spacing ratio and value of the powder factor for breaking the near-contour rock layer.
3.  The proposed method provides the possibility of a calculated estimate of the expected quality of contouring the working for given mining conditions.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 4, pp. 31–32, April, 1990.  相似文献   

20.
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   

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