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Hydrotechnical Construction, Vol. 34, Nos. 8-9, 2000 THE SCIENTIFIC BASIS FOR DESIGNING AND BUILDING HYDRAULIC STRUCTURES S. O. Britvin and L. A. Zolotov Careful research is needed on building HES because of the uniqueness of the structures and their equipment, particularly in relation to the variety of natural conditions. Research is needed in designing and building such plant and major water-handling systems because of the following conditions: the tendency to exploit hydroelectric resources in regions having difficult natural conditions, the need to provide high reliability and safety in the structures, the need to provide elevated economy in the use of hydroelectric energy by comparison with alternative sources, and the need to reduce the adverse effects of the plant on the environment. Those circumstances have made it necessary to carry through research as an essential part of the design and as the decisive factor in improving the engineering design and economic performance of hydroelectric engineering, which was the case in the Soviet Union from as long ago as the 1930s. At that time, research laboratories were set up directly at major constructional sites such as the White Sea-Baltic Canal, the Uglich and Rybinsk reservoirs on the Volga, and the construction of the Moscow-Volga Canal. In the postwar period, a large volume of research was required on designs for very large structures, which made it of particular importance to have a unified center in place of research laboratories at the various large constructional sites. A proposal from the Council of Ministers of the USSR dated 30 June 1949 set up the Research Center under Gidroproekt and gave it the rights of a research center of Union significance. In 1991, the rising need to carry out research on thermal and nuclear power stations led the USSR Ministry of Energy to rename that center as the Power Structure Research Institute. In the 1950s and 1960s, the activities of the Institute were concentrated on providing high reliability and good economy in large hydroelectric structures built on rivers in plains in the European part of the Soviet Union. Comprehensive laboratory and field studies were made on very large hydroelectric stations in the Volga-Kama and Dnepr cascades, and also on large ship navigation canals. In the 1970s to 1980s, the center of gravity in Russian hydroelectric construction shifted to high-pressure stations in Siberia, the Russian Far East, Central Asia, and Transcaucasia. A scientific basis was provided for the designs and documentation for the construction in such notable plant as the rock-filled dam at the Nurek HES, the arch dam at the Inguri HES, and the gravitational concrete dam at the Toktogul’ HES, as well as many others, which up to now have had no analogs in world hydroelectric construction. Comprehensive researches have been performed in designing and building all plant for foreign countries, whose development was provided by the head institute. In the 1980s, in connection with the Gidroproekt designing of nuclear power stations, the Institute was charged with providing the scientific packing to the nuclear station projects. In the 1990s, a considerable volume of research was done on the safe operation of hydroelectric stations, including the development of methods and means of diagnosing the states of the structures, as well as the development and installation of monitoring systems. The Institute was named as the head organization for the sector program on safety in power construction. The Gidroproekt researches involved extensive participation of design and study sections at the Institute. To conduct the researches, assistance was received from research institutes in related sectors (All-Union Geological Research Institute, Georgian Hydroelectric System Research Institute, and the Electrical Power Research Institute), in addition to assistance from institutes under the USSR Academy of Sciences, those in the Union republics, and also from higher educational institutions (Moscow Power Institute, Leningrad Polytechnical Institute, and so on). The research center provided the scientific basis for projects undertaken by the head institute and by the Central Asian and Ukrainian sections. The Kazakh and Kuibyshev branches of Gidroproekt also carried out general coordi- nation of research in the Gidroproekt Institute system. The All-Union Geological Research Institute was the leading organization in providing the scientific basis for projects drawn up by the Leningrad division, while the Georgian Hydroelectric Power System Research Institute was responsible for those designed by the Tbilisi branch. In the years that the Institute has existed, it has grown into a large scientific organization involved directly in developing Russian power engineering and hydroelectric construction in particular, in which it has acquired Translated from Gidrotekhnicheskoe Stroitel’stvo, Nos. 8-9, pp. 14-19, August-September, 2000. 0018-8220/00/3489-0385$25.00 c 2001 Plenum Publishing Corporation 385

The Scientific Basis for Designing and Building Hydraulic Structures

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Page 1: The Scientific Basis for Designing and Building Hydraulic Structures

Hydrotechnical Construction, Vol. 34, Nos. 8-9, 2000

THE SCIENTIFIC BASIS FOR DESIGNING AND BUILDINGHYDRAULIC STRUCTURES

S. O. Britvin and L. A. Zolotov

Careful research is needed on building HES because of the uniqueness of the structures and their equipment,particularly in relation to the variety of natural conditions. Research is needed in designing and building such plantand major water-handling systems because of the following conditions: the tendency to exploit hydroelectric resourcesin regions having difficult natural conditions, the need to provide high reliability and safety in the structures, theneed to provide elevated economy in the use of hydroelectric energy by comparison with alternative sources, and theneed to reduce the adverse effects of the plant on the environment. Those circumstances have made it necessary tocarry through research as an essential part of the design and as the decisive factor in improving the engineering designand economic performance of hydroelectric engineering, which was the case in the Soviet Union from as long ago asthe 1930s. At that time, research laboratories were set up directly at major constructional sites such as the WhiteSea-Baltic Canal, the Uglich and Rybinsk reservoirs on the Volga, and the construction of the Moscow-Volga Canal.In the postwar period, a large volume of research was required on designs for very large structures, which made itof particular importance to have a unified center in place of research laboratories at the various large constructionalsites. A proposal from the Council of Ministers of the USSR dated 30 June 1949 set up the Research Center underGidroproekt and gave it the rights of a research center of Union significance. In 1991, the rising need to carry outresearch on thermal and nuclear power stations led the USSR Ministry of Energy to rename that center as the PowerStructure Research Institute.

In the 1950s and 1960s, the activities of the Institute were concentrated on providing high reliability andgood economy in large hydroelectric structures built on rivers in plains in the European part of the Soviet Union.Comprehensive laboratory and field studies were made on very large hydroelectric stations in the Volga-Kama andDnepr cascades, and also on large ship navigation canals. In the 1970s to 1980s, the center of gravity in Russianhydroelectric construction shifted to high-pressure stations in Siberia, the Russian Far East, Central Asia, andTranscaucasia. A scientific basis was provided for the designs and documentation for the construction in suchnotable plant as the rock-filled dam at the Nurek HES, the arch dam at the Inguri HES, and the gravitational concretedam at the Toktogul’ HES, as well as many others, which up to now have had no analogs in world hydroelectricconstruction. Comprehensive researches have been performed in designing and building all plant for foreign countries,whose development was provided by the head institute. In the 1980s, in connection with the Gidroproekt designing ofnuclear power stations, the Institute was charged with providing the scientific packing to the nuclear station projects.In the 1990s, a considerable volume of research was done on the safe operation of hydroelectric stations, includingthe development of methods and means of diagnosing the states of the structures, as well as the development andinstallation of monitoring systems. The Institute was named as the head organization for the sector program onsafety in power construction.

The Gidroproekt researches involved extensive participation of design and study sections at the Institute.To conduct the researches, assistance was received from research institutes in related sectors (All-Union GeologicalResearch Institute, Georgian Hydroelectric System Research Institute, and the Electrical Power Research Institute),in addition to assistance from institutes under the USSR Academy of Sciences, those in the Union republics, andalso from higher educational institutions (Moscow Power Institute, Leningrad Polytechnical Institute, and so on).The research center provided the scientific basis for projects undertaken by the head institute and by the CentralAsian and Ukrainian sections. The Kazakh and Kuibyshev branches of Gidroproekt also carried out general coordi-nation of research in the Gidroproekt Institute system. The All-Union Geological Research Institute was the leadingorganization in providing the scientific basis for projects drawn up by the Leningrad division, while the GeorgianHydroelectric Power System Research Institute was responsible for those designed by the Tbilisi branch.

In the years that the Institute has existed, it has grown into a large scientific organization involved directlyin developing Russian power engineering and hydroelectric construction in particular, in which it has acquired

Translated from Gidrotekhnicheskoe Stroitel’stvo, Nos. 8-9, pp. 14-19, August-September, 2000.

0018-8220/00/3489-0385$25.00 c©2001 Plenum Publishing Corporation 385

Page 2: The Scientific Basis for Designing and Building Hydraulic Structures

recognized authority and acceptance throughout the scientific world. In the mid-1980s, the staff at the ResearchCenter numbered over 1500, of whom 100 were DScs and PhDs, 650 scientific workers, and over 400 assistants. Therewere 24 research sections located over an area of 11 hectares; the total area of the laboratory buildings was more than40 thousand m2. The Research Institute had research sections containing laboratory and experimental facilities inVolgograd and Gorodtse, as well as various field groups at large construction sites such as the Nurek, Charvak, andCheboksary hydroelectric stations, the Toktogul’ station, the Zagora pumped-storage station, in the construction ofthe KAMAZ, and other plant.

The researches were designed for the execution of government programs for developing power engineeringand water management in the country, and thus providing a basis for designs and scientific backing for implementingthe construction, while also providing monitoring of the structures under field conditions and providing the scientificbasis for governmental, sector, and departmental standardization documents in hydroelectric construction. Fruitfulcollaboration between the designers and researchers in the Gidroproekt Institute system led to the definition of a firmrule: no important or difficult engineering decision can be taken without support from laboratories and calculationson a theoretical basis. During the period of its activities, the Institute has performed theoretical, experimental,and field studies for more than 300 hydroelectric and water-management projects dealt with by the GidroproektInstitute, as well as projects for thermal and nuclear power stations. The volume of costs for research in the Institutein 1970-1980 was up to 12% of the total cost.

The researches have led to the publication of 120 books, while leading scientific journals and collections ofarticles in the country have included more than 4500 papers; about 3000 reports have been presented at conferences,symposiums, and meetings. The scientists at the Institute have performed hundreds of developmental studies,and many of them have formed the basis for outstanding engineering designs, which have been amongst the leadingachievements of world hydroelectric construction. It is not possible in this paper to deal even with the most substantialof them, and we can merely give some examples of solutions obtained to problems that in our opinion serve tocharacterize the activities of the major scientific divisions.

Amongst the researches on building on soft erodable bases, there were ones providing data on materials forcovering river beds and developments in the technology of frontal and rear covering. The best design for downstreamspillways on soft rocks required research on turbulent flows. In research on ship navigation structures, hydraulicsystems for supplying locks were developed; research was done on the water conditions in lock chambers equippedwith various filling and draining systems, as well as on the behavior of ships in locks, as well as at the approaches tothem. In the design and construction of high-dam units in Siberia, the Far East, Central Asia, and Transcaucasia,there were problems with fast flows such as absorbing the flow energy, cavitation, abrasion, aeration, and rock erosiondownstream.

The most important results were obtained on the cavitation mechanism, cavitation conditions, materialcavitation resistance, and measures to protect structures from cavitation damage. Infiltration phenomena wereresearched and measures to prevent them were developed for major rock-fill and concrete dams. Numerical methodswere developed for determining floodwater parameters. Experience accumulated in these researches on Russian highdams provided effective designs for use abroad, including tunnel discharges at the Teri HES in India and the LijashaHES in China, which involved flow spiraling to absorb much of the energy within the tunnel and thus prevent damageto the sides of the narrow channels on discharge of fast flows because of the optimization of the end-section shapesat Kapanda HES in Angola and Kausar in Iran, as well as some others. Hydroelectric structures were designed forthe Nile in Sudan, and derivation HES in the North Caucasus made it important to manage drift flows.

Equipment component researches for nuclear stations containing various types of reactor were concernedwith hydraulic factors in order to provide safety at the stations. These tasks related to poorly researched areasin the mechanics of liquids and lay at the interfaces with other sciences: nuclear physics, thermodynamics, andstructure dynamics. Methods were devised for evaluating the conditions occurring in emergency containment spacesand arising from coolant escape. Various hydraulic components for nuclear stations were developed and tested, suchas gravitational and centrifugal steam separators, buffer vessels, multilayer pressure vessels, and so on, many of whichwere recorded as inventions.

The Institute researched concrete and ferroconcrete structures in concrete dams, HES buildings, undergroundstructures, locks, and in ferroconcrete and steel-reinforced pipes. Industrial methods were developed for construction,and new technologies were devised for raising structures. These research results provided the basis for the assemblyof the main structures at Saratov HES, which involved handling ferroconcrete components of mass up to 200 t;they also had a bearing on the states of stress and strain in the dam at Toktogul’ HES, which involved a methodof layered concrete use; steel-reinforced pipes were also used at Zagora and Kaishyador pumped-storage stations;and various design studies and calculations were performed on new technologies for the industrial building of Kurskand Smolensk nuclear power stations. In order to mechanize the work and reduce the building times, designs weredeveloped for finned reinforcing panels for fixed facing. Those panels were used in the walls and roofs of nuclear station

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containment. In the 1970s and 1980s, experimental and theoretical researches on a large scale were performed on thepressure vessels for combined heat and power nuclear stations, which employed prestressed ferroconcrete, which wasalso employed in the station shielding. During the last decade, the Research Center has performed comprehensivestudies on steel-reinforced pipes and spiral turbine chambers, which enable one to evaluate the state of strain in themin stress concentration zones, as at the Al Vakhda HES (Morocco) and the Three Gorges station in China. Muchwork was done to strengthen and repair the lock walls on the Moscow Canal.

In the technology of concrete and other building materials, researches have been done under laboratoryconditions and directly at construction sites. New types of vibrator have been introduced together with the SSBplasticizer and a method of using unheated cold concrete and another for laying concrete whose maturing time isup to 90 days; it was shown that hydroelectric structures can be built by the use of plates and shells. Researcheswere done on polymers such as epoxide resins for cementing concrete, hydraulic isolation, fastening reinforcement,and for rendering concrete structures monolithic. Research on cavitation and wear resistance for concrete at highdams led to the development of good compositions for polymer mastics, solutions, and concretes for protecting andrepairing concrete in the case of cavitation and erosion by drifts, which have been used at the Bratsk, Charvak,Nurek, Cheboksary, Nizhnekama, and Sayan-Shushen HES. Building structures at nuclear power stations have beenprotected by the use of radiation-resistant paint polymer coatings that can be deactivated, as well as jointless pouredepoxide-rubber coatings for floors, and technologies for using rapid-setting plastic cement-sand solutions for buildingleveling sections under the floor.

These various field and laboratory researches on earth materials and structures led to the development ofmethods and equipment for recording the dynamic characteristics of soil materials, as well as programs definingthe states of stress and strain in dams with due allowance for the plasticity of the soil, in addition to methods forlarge-scale research on the limiting states of dams under static and dynamic loads. Considerable advances were madein researching the behavior of soils and the basements of hydraulic structures in permafrost zones. The centrifugalsimulation method was applied to the Nurek, Rogun, Kureia, Vilyuy, Hoabinh, and other HES to resolve manyproblems in designing and building earth-fill structures, such as the carrying capacity of an inhomogeneous base,cracking criteria for the core of a dam, flank stability, and soil pressure on structures.

Researches were also done on underground structures and technologies for forming them, which confirmedthat facing not particularly resistant to cracking can be used in hydrotechnical construction. A large-scale testerwas applied to constructions for combined facings for pressurized tunnels, together with economical load-bearing andreinforcing concrete facings for these tunnels in combination with anchoring. Light-weight structures for reinforcingthe walls of chambers have been used in underground machine bays at the Ingur, Zhinval’, Kolyma, Rogun, andHoabinh HES. The principal line of calculations involved abandoning laborious hand methods applied to staticallyundetermined systems and transferring to computer technologies. Numerous programs were written for undergroundstructures, which defined the state of stress and strain in facings and in the surrounding rock. A comprehensivetechnique was devised for designing underground machine halls, which was based on finite-element methods andincluded simulation on equivalent materials, as well as the use of measurements under field conditions.

Numerous laboratory and field researches were performed on HES equipment (the energy parameters, cav-itation, vibration, and hydraulic effects), which provided universal characteristics for turbines, which were used inrefining the working characteristics of the turbines at many HES. These researches were used by agreement withmanufacturers to increase the unit power in the Lenin Volga HES and the Volgograd HES from 105 to 115 MW. Theturbine unit laboratory not only researched many Russian and foreign installations but also was the first to researchtransient response in the Aswan HES. Large-scale model studies were applied to the four-unit block at Chirkei HES,in which the units are arranged at two levels and which gave scope for deriving the characteristics of the flow in theexit sections, together with the kinematic and dynamic characteristics of the flow within the turbines; this providedestimates of the interaction between the turbines in that block of two-level structure for various combinations ofthe working and idling turbines. These researches defined the working states in the Chirkei HES and were used inbuilding the Toktogul’ HES in Kirgizia and the Lijasha HES in China. Numerous theoretical and working studiesdemonstrated that direct asynchronous startup is possible for the generator-motor at Zagora pumped-storage stationoperating from the line provided that it is fitted with massive rotor poles. Research on raising generator voltages ledto the manufacture of the first 110 kV generator providing 14.5 MW, which was installed and tested at SkhodnyaHES. Methods were developed for comprehensive field tests, for which equipment was built, which was used overmany years in acceptance testing of head specimens of hydroelectric equipment for HES on the Volga, Dnepr, Angara,Naryn, and Vakhsh, as well as at many foreign power stations.

The main lines of research on nontraditional renewable energy sources at the Institute have been wind power,tidal energy, and small HES. Use was made of all methods for physical simulation on laboratory testers and inthe field, as well as mathematical simulation methods, partly because advances had been made in computationalhydrodynamics and the Institute possessed what was at that time a fairly powerful computing center. Several designs

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were developed and manufactured for a wind-power plant having a vertical shaft and aerodynamic speed regulationto give power from 1 to 5 kW, three of which pass tests on a wind farm at Dubkakh (Dagestan). In the areaof tidal energy, the researches were concerned mainly with the experimental Kislogub tidal power station, wheremeasurements were made on the working conditions and on the conditions in the thin-walled reinforced-concretestructures in the corrosive seawater, which gave valuable evidence for marine hydrotechnical construction. In 1995-7, various researches were performed in connection with the design, manufacture, transportation, installation, andcommissioning of three automated MEG-250 units for a small HES on the R. Razdan in Armenia. That HES hadan installed power of 750 kW and has been in use since it was commissioned in July 1997.

There have been two lines of systematic research on dynamic phenomena in hydrotechnical structures: work-ing dynamic loads on the one hand and strength and stability of the structures and the components in them underthose loads on the other. Methods have been developed for the quantitative forecasting of seismic effects on largedams, which make use of the geological and seismic data on the region, the random occurrence of earthquakes with agiven intensity, and the random variations in the quake parameters for given macroseismics. A linear spectral methodhas been brought to perfection for estimating the seismic resistance of dams. The most important scientific result incalculations on dams is that wave methods have been developed for estimating seismic deformations in structures.These methods have been used with others in various combinations in designing very large dams in the USSR andelsewhere. Many changes have been made in the design of the dams to improve the reliability, and in particular,antiseismic reinforcement was used near the crest of the Nurek dam.

Safety in power structures has occupied and still occupies a leading place in the Institute’s researches.Methods have been devised for safety evaluation, in which one of the central aspects of working monitoring is thedetermination of structure safety criteria. A method has been developed for estimating the safety level of existingstructures in the form of a generalized parameter that combines the effects of quantitative and qualitative safetycharacteristics. These deep researches have enabled the Research Center to participate as the head organization inthe drafting of the Federal law ”Hydrotechnical structure safety.”

Reliability and safety have been provided in power structures by means of field observations on them, whichhave employed instrumental and visual checks. Field observations and researches have been done on 60 HES andpumped-storage stations, including 15 foreign ones and 6 nuclear stations containing reactors of VVER-1000 type.

Field research over many years has revealed some features of these structures:1) observations on the settlement of concrete structures founded on smooth bases can be used to refine the size

of the active compressed zone and have given an evaluation of how soil creep affects the final value of the settlement;2) to determine the state of stress and strain in a concrete dam by strain-gauge methods, which are necessary

right from the start of construction, it has been found possible to use the analogous elastoplastic characteristics ofconcrete derived earlier from the construction of high dams;

3) monitoring data on the temperatures in the concrete blocks have led to recommendations on the bestintervals for laying concrete in adjacent blocks, as well as the intervals and durations for forced cooling and the bestintervals for cementing the joints;

4) infiltration observations indicate how the permeability of the concrete and the draining action of the wateraffects HES buildings and the dams containing them when they are located on largely impermeable clay or craggysubstrates, as well as how changes in the state of stress and strain in the contact zone of the basement in a highconcrete dam affects the infiltration; and

5) field tests on nuclear station protection during the first five years of operation allow one to forecast theloss of prestress on prolonged operation and to establish the periods required for restressing the shields.

A major line has been the development of monitoring equipment for field researches and diagnosis of structuresunder construction or in use. Not only has such equipment been developed for field observations, but also unique planthas been introduced for model researches. Particular purposes have been to build sensors for use in existing workingstructures and to extend the volume of regular production of string sensors, as well as providing metrological supportto their production and use. Research has also been done on metrological support to monitoring structures andbasements. In 1981, a prize was awarded by the USSR Council of Ministers for the researches on the creation, support,and general implementation of methods and means of monitoring the structure and equipment reliability at HESand pumped-storage stations, which the Research Center has carried out in collaboration with other organizations.

Much has also been done on researching and resolving ecological problems in hydrotechnical construction,particularly to estimate the current state of the environment in any region around an HES either proposed, underconstruction, or in operation; this is designed to forecast any changes in the state produced by the structures andthus to draw up and implement conservation measures, and also to prepare documents on the protection of theenvironment and the proper use of natural resources in the regions where hydroelectric stations are being builtor operated. The ecological aspects have been researched for more than 80 HES projects in the Soviet Union andelsewhere. A particular place is taken by researches on the ecological state of water sources in the Moscow region such

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as evaluating water quality in the reservoirs on the Moscow Canal in connection with the reconstruction of it, andforecasting surface water quality within the scheme for providing Moscow region with water, with recommendations onprotecting the sources; and ecological research on the principal areas for building pumped-storage stations in Moscowregion, estimating the effects of the Zagora pumped-storage station on the microclimate, the aqueous environment,and adjacent areas, and devising environmental protection measures for the Pakhra structure; there have also beenevaluations of ecological conditions on the R. Skhodnya and so on.

The laboratory studies were performed on systems built at the Institute, which were equipped with precisionmeasuring equipment. Much of this apparatus was developed and made at the Institute itself, but an obligatorycondition for using it was that it should pass government certification. The theoretical studies were performed atthe Institute’s computing center, which was equipped with computers that were the latest for their time.

From 1991, much of the research science, apart from the geodynamic observations, was conducted in a separateresearch institute, the Electrical Power Systems Research Institute Incorporated, which was set up on the basis of theGidroproekt Research Center. That separation between the design and research parts of Gidroproekt was occasionedby the restructuring of the country’s economy, and was relatively painless because the two are separated in area, andultimately it was found justified. In particular, the new Institute had state accreditation as a scientific organization,which gave the organization some tax advantages and the right to set up specialized councils to consider dissertationsand also to train graduate students. On the basis of current legislation, the single organization of Gidroproekt withits Research Center could not have been considered for state accreditation as a scientific institution. In spite of thelegal distinction between the design and research parts of Gidroproekt, all the links between those parts developedover decades have not weakened (technological, production, data, and human resources), and they have merely beentransformed in the spirit of the time. One can say definitely that the linkage between the Gidroproekt and the newInstitute represents a single scientific design association capable of handling tasks at the highest level of difficulty inhydraulic engineering and hydroelectric power construction.

Since the new Institute was established, the following basic scientific operations have been undertaken tomeet orders or on behalf of Gidroproekt:

1990-1. Preparation of SNiP 2.06.12 ”Reservoirs and environmental protection.” This gives the basic designprinciples; there have also been comprehensive researches on the Alychan and Boguchan HES, the Zagora pumped-storage station, the Inguri HES, the Kaishyador pumped storage station, the Katun and Plyava hydroelectric stations,the Tugur tidal power station, Tsimlyan HES, the Kapanda installations, the Mzhara HES, and also the Teri andTishrin ones; and also the writing of programs for CAD.

1992-3. Comprehensive researches on Boguchan HES, Zagora pumped storage station, Inguri HES, KatunHES, the Koloch installation, the Plyava and Tsimlyan HES, the Kapanda installation, the Teri HES and pumped-storage station, the Koteshvar and Khordada installations, and the Yali HES.

1994-5. Comprehensive researches on the Al Vakhda installation, the Aushiger and Boguchan HES, Zagorapumped storage station, the Koteshvar and Merove installations, Plyava HES, the Tishrin and Khordada installations,Tsimlyan HES, and Yali installation; there was also research on units containing transverse-jet turbines and thedevelopment of methods for measuring the insulation parameters of hydraulic generator stators.

1996-7. Research on drift erosion conditions ahead of the backup water intake at Aushiger HES; revisingthe documentation on the equipment at Boguchan HES, particularly the monitoring and measuring instruments,on account of the reduction in the dam crest level; monitoring the effects of Zagora pumped storage station on theenvironment; developing concrete resistant to long-time abrasive and impact wear by ice for the conditions of theMezen tidal power station; researching the conditions downstream from the Merove installation when streams arereleased from the dam sluices; experimental researches on silting in reservoirs and the transmission of drifts throughthe Nizhnecherek HES; and calculations on the dam at Kazhbar installation.

1998-2000. Model hydraulic studies on the HES-pumped storage conditions at Teri upstream of the dam,hydraulic studies on the emergency gates on the power tunnel at Teri HES, supervision of the measuring equipmentlocation in the early parts of the Teri HES-pumped storage structures, evaluating biological growths on structuresand equipment in the water supply to the Kudankulam nuclear power station, and researches on the conditions fortaking in and discharging technical water at Kudankulam nuclear power station.

The close coordination of operations between Gidroproekt and the new Institute has been predetermined bythe technology involved in designing hydroelectric installations.

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