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EN
Based on theoretical and long-term field researche, the article provides assessment of the management of engineering and technical structures of the Zhinvali hydroengeneering complex. The methodology and quantitative assessment of the risk of loss resulting from accidents at hydraulic structures are de-scribed. The implementation of the recommendations of scientific researche related to the protection of the waters of the Zhinvali reservoir will allow to extend its service life for at least another twenty years, which, subject to one-time-only investments in protection measures in the amount of 35 million GEL (1 USA Dollar - 2,90 GEL), will provide an opportunity to bring the amount of direct and indirect loss prevented to 25 million GEL per year. The calculation showed that rational management of the reservoir will allow, with an internal rate of return (IRR) of 42%, to accumulate net present value (NPV) in the amount of 87.6 million GEL over twenty additional years of operation, which in turn indicates a high efficiency of investments in the protection of reservoir waters.
EN
Changes in river channel morphological parameters are influenced by anthropogenic factors, such as climatic changes, river catchment management changes, and hydrotechnical development of rivers. To assess the intensity of individual pressures and the resulting changes in abiotic and biotic factors in the riverbed, water quality monitoring is conducted, including the assessment of the hydromorphological status. The assessment can be based on the River Habitat Survey (RHS) which is a synthetic method that includes the evaluation of habitat character and river quality based on their morphological structure. The input data, which characterise any river include physical features of hydrotechnical structures, bed granulation, occurrence of bedforms, visible morphodynamic phenomena, and a sediment transport pattern. The RHS method allows to determine two quantitative indices used to evaluate the hydromorphological status: Habitat Modification Score (HMS), which determines the extent of transformation in the morphology of a watercourse, and Habitat Quality Assessment (HQA), which is based on the presence and diversity of natural elements in a watercourse and river valley. The proposed method can be divided into three stages. The first assesses the river section hydromorphological indices, describing the degree of technical modification (HMS) and the ecological quality of the reach (HQA), using the RHS method. The second stage describes morphological changes resulting from the technical regulation and estimates indices for the regulated reach. Finally, we compare HQA and HMS indices before and after the regulation. This comparison is described by numerical indicators and related to reference values.
EN
The paper studies the relationship between the ambient temperature change and the horizontal displacements on control points ofthe Dnieper Hydroelectric Station dam from 2016 to 2020. A specially developed software product analyzed the GNSS time series ofmeasurements pre-processed by the GeoMoS system to determine the parameters of seasonal displacements and theirrelationship with seasonal changes in air temperature. The research established that the influence of ambient temperature in theabsence of significant changes in the water level in the upper reservoir determines the cyclicity of dam deformations. It isestablished that the projections of velocity vectors of reference points in the ETRF-2014 system for the studied period do notexceed the absolute value of 3 mm/month. The directions of the horizontal displacement vectors in the first half of each year areopposite to the directions recorded in the second half. In the first half of the year, the dam’s body shifts towards the reservoir,while in the second half year period, it shifts-backwards. According to the three-year GNSS monitoring of the DnieperHydroelectric Station dam, the amplitude of semi-annual horizontal oscillations of the control points relative to the dam axis isfrom -9.5 to +8 mm. In winter and summer, the horizontal displacements increase from the edges of the dam to its central part,and the amplitudes of the horizontal displacements move vice versa. The obtained data establish a linear analytical relationshipbetween the average temperature and the horizontal displacements of the GNSS control points.
EN
The article presents the problem of symbiosis between hydraulic structures and the natural landscape. The necessity of the engineering intervention in natural water cycle and resulting consequences have been indicated. Much attention has been paid to the issue of environmental compensation and the visual adaptation of the hydrotechnical facility to the surrounding landscape, referring to selected hydrotechnical solutions.
PL
W artykule poruszono problem symbiozy między budownictwem hydrotechnicznym, a krajobrazem naturalnym. Wykazano konieczność ingerencji w naturalny obieg wody w przyrodzie oraz przedstawiono wynikające z niej konsekwencje. Dużą uwagę poświęcono kwestii ochrony środowiska tj. kompensacji przyrodniczej oraz wizualnego przystosowania obiektu hydrotechnicznego do otaczającego go krajobrazu. Ponadto ukazano możliwość współistnienia przemysłu i natury powołując się na wybrane rozwiązania hydrotechniczne.
EN
The paper presents results of hydraulic modelling of block ramps (BR) made of natural stones (seven constructional solutions) and compares them with the results of classical research by Peterka. The main aim of the paper is to provide a simplified solution to determining the dimension of stones fixed to the sloping apron of the BR in order to reduce energy of flowing water along the ramp. This new way of assessing the dimensions of stones along BR sloping apron is presented with proposals on how to calculate stone dimension. The paper is dedicated to hydraulics engineers, scientists, designers, practitioners and also to researchers in the field of low-head hydraulic structures.
PL
W artykule przedstawiono sposoby prowadzenia analizy stanu naprężenia i odkształcenia dla betonowych konstrukcji hydrotechnicznych przy wykorzystaniu metody elementów skończonych. Omówiono wpływ termiki na przemieszczenia i naprężenia powstające w masywnej betonowej konstrukcji przy etapowym betonowaniu obiektu oraz w cyklu wieloletnim w czasie eksploatacji. Przedstawiono warunki prowadzenia analizy nieustalonej oraz wprowadzono zależności dla modeli 2D i 3D pomiędzy przyjętym krokiem czasowym a wielkością elementu w modelu, zapewniające poprawność rozwiązania.
EN
The article presents various ways of carrying out analysis of the state of stress and deformation of concrete hydraulic structures using the finite elements method. It discusses the influence of thermals on dislocations and stresses occurring in the massive concrete structure while pouring concrete in stages as well as in a multi-annual operational cycle. It presents the conditions for carrying out the unspecified analysis and introduces correlations for the 2D and 3D models between the adopted time step and the size of the modelled element, ensuring the correctness of results.
EN
The flow field of many practical open channel flow problems, e.g. flow over natural bed forms or hydraulic structures, is characterised by curved streamlines that result in a non-hydrostatic pressure distribution. The essential vertical details of such a flow field need to be accounted for, so as to be able to treat the complex transition between hydrostatic and non-hydrostatic flow regimes. Apparently, the shallow-water equations, which assume a mild longitudinal slope and negligible vertical acceleration, are inappropriate to analyse these types of problems. Besides, most of the current Boussinesq-type models do not consider the effects of turbulence. A novel approach, stemming from the vertical integration of the Reynolds-averaged Navier-Stokes equations, is applied herein to develop a non-hydrostatic model which includes terms accounting for the effective stresses arising from the turbulent characteristics of the flow. The feasibility of the proposed model is examined by simulating flow situations that involve non-hydrostatic pressure and/or nonuniform velocity distributions. The computational results for free-surface and bed pressure profiles exhibit good correlations with experimental data, demonstrating that the present model is capable of simulating the salient features of free-surface flows over sharply-curved overflow structures and rigid-bed dunes.
PL
W artykule przedstawiono rys historyczny powodzi w XIX wieku, proponowany projekt Przekopu, przebieg jego realizacji i konsekwencje, towarzyszące mu budowle hydrotechniczne i regulacyjne oraz konieczność dysponowania sprawną organizacją lodołamania. Przedstawiono również rozwój stożka usypowego, jaki powstał po wykonaniu Przekopu, i obecny stan końcowej części Przekopu.
EN
The article presents the historical outline of floods in the 19th century, the proposed Cross-cut project, course of its implementation and its consequences, as well as the accompanying hydro-technical and regulation facilities and the need to have an efficient ice-breaking organization. It also present the development of the talus cone created after the Cross-cut was completed and the current state of the terminal part of the Cross-cut.
PL
W pracy omówiono problemy ochrony przeciwpowodziowej rzek Karpat Ukraińskich. Zwrócono uwagę na potrzebę przeprowadzenia kompleksowej regulacji rzek wraz z realizacją: projektowanych zbiorników wodnych retencyjnych (przeciwpowodziowych), wałów ochronnych, budowli wodnych piętrzących (struktur regulacyjnych). We wnioskach podniesiono konieczność (potrzebę) wsparcia badań naukowych związanych z kompleksową oceną skutków wynikających z regulacji rzek. Zakres badawczy powinien obejmować badania naukowe na odtworzonych budowlach wodnych (tzw. modelach fizycznych) w połączeniu z modelowaniem układów (struktur) hydraulicznych wraz z wykonaniem obliczeń matematycznych dotyczących prognozowania skutków regulacji koryt rzecznych (cieków).
EN
This work concerns the problem of flood control of rivers in the Ukrainian Carpathians. It points to the need of carrying out comprehensive river engineering altogether with the execution of the designed flood reservoirs, flood banks and hydraulic structures (river regulation structures). The conclusions indicate the necessity to support scientific research related to a comprehensive assessment of the effects of river engineering. The research should include scientific studies of reconstructed hydraulic structures ( so called physical ones) , as well as the modelling of hydraulic structures and mathematical calculations concerning the prognosis of the effects of watercourse engineering.
11
PL
Analiza wyników badań nad wpływem czasu zainstalowania oraz struktury jedno- i dwuwarstwowych geowłóknin otrzymywanych techniką spun-bonded na wybrane właściwości fizyczne i hydrauliczne wyrobu. Oznaczenie wpływu czasu użytkowania oraz zakolmatownia geowłóknin na zmianę wodoprzepuszczalności prostopadłej do wyrobu bez obciążenia.
EN
Results of studies of the effect of the operating time and structure of one-layer and bilayer spun-bonded geotextiles for hydraulic engineering, on selected physical and hydraulic properties. Analysis of the effect of the operating time and colmatation on the perpendicular water permeability of geotextiles without load.
12
Content available remote Scour downstream of J-Hook vanes in straight horizontal channels
EN
J-Hook vanes are grade control structures used to stabilize the riverbed. This paper aims to investigate the behaviour of J-Hook vanes as a grade-control structure in straight rivers. Scour downstream of J-Hook vane structures like other grade-control structures depends on the shape of the structure and the river hydraulic conditions. The purpose of this study is classifying the scour geometry and predicting the main scour parameters such as the scour depth, length, width, and the ridge height and length downstream of the J-Hook vanes in straight rivers. Experiments were carried out in a horizontal channel. For each length of the structure, three heights in different hydraulic conditions, including densimetric Froude numbers, water drops, and opening ratios, were tested. Results show that the densimetric Froude number, the drop height, and the height of the structure are the key parameters to form and classify the scour. Equations have been derived using dimensional analysis and experimental data to predict the maximum scour depth, the maximum length of the scour, the maximum scour width, and the maximum height and length of the dune. All the experiments were conducted in clear water conditions.
PL
Kanał Łasica jest głównym ciekiem odwadniającym w obszarze Kampinoskiego Parku Narodowego. Analizowano możliwość wykorzystania istniejących i projektowanych budowli na kanale Łasica do utworzenia zalewów i zwiększenia retencji wodnej przyległego do niego obszaru i poprawy warunków uwilgotnienia gleb. Rozważano spłycenie i zmniejszenie przekroju poprzecznego kanału Łasica, w celu ograniczenia jego drenującej roli w warunkach ograniczonych zasobów wody, połączone ze wznoszeniem progów stałych do podwyższenia poziomu wód w kanale.
EN
The Łasica Canal is the main draining watercourse in the area of the Kampinoski National Park. Chances of using the existing and planned buildings on the channel were analyzed in the light of creating water reservoirs and increasing water retention in the adjacent areas as well as improving soil humidity. Actions aiming towards shallowing the channel and reducing its cross-section dimensions were considered to limit its role in the drainage conditions in the areas with limited water resources, combined with installing the thresholds that can cause increase of water level in the channel.
PL
Ze względu na rozmiary masywnych budowli hydrotechnicznych z betonu i ich blokową strukturę lokalizacja spękań, szczególnie od strony odwodnej budowli, oraz spękań wewnętrznych wymaga zastosowania skomplikowanych technik diagnostycznych.
PL
Przedstawiono układ hydrauliczny automatycznej czyszczarki krat zapory wodnej. Opisano także zabudowę urządzenia na obiekcie zapory, podając ogólną zasadę działania i cykle pracy czyszczarki. Wyróżniono mechanizmy hydrauliczne: opuszczania i podnoszenia zgarniacza, jazdy czyszczarki oraz otwierania i zamykania zgarniacza.
EN
The thesis refers to hydraulic system of automatic grate cleaner on dam. Development of equipment on dam and basic elements, as well as general principles of operation and cleaner work cycles has been presented. There are marked out the hydraulic mechanisms: opening and closing of scraper, cleancr travel, lifting and lowering of scraper.
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