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Tytuł:
Assessment of submerged floor water jets to minimize the scour downstream from a stepped spillway
Autorzy:
Ibrahim, Mohamed M.
Diwedar, Al Sayed Ibrahim
Ibraheem, Ahmed Mahmoud
Powiązania:
https://bibliotekanauki.pl/articles/1841974.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
floor jets
flume
jet rows
stepped spillway
scour depth
scour length
Opis:
Because of hydraulic jump, the scour downstream a stepped spillway is the most confusing issue that endangers the overall stability of the spillway. In this paper, thirty-six exploratory runs are described to explore the impact of utilizing submerged water jets fixed in the stilling basin of a stepped spillway on the downstream scour measurements under various flow conditions. A smooth apron where the water jets are disabled is incorporated to characterize the impact of adjustments studied. Trials are performed utilizing different upstream discharges, jets arrangements, and tailwater depths. The results are analyzed and graphically presented. The experimental data are contrasted to a scour formulae developed by other specialists. Outcomes indicated that by utilizing submerged floor water jets, the maximum scour depth is decreased between 14.3 and 36.0%. Additionally, the maximum scour length is reduced by 9.7 to 42.3%. Finally, involving regression analysis, simple formulas are developed to estimate different scour parameters.
Źródło:
Journal of Water and Land Development; 2021, 50; 122-129
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The study of the local scour behaviour due to interference between abutment and two shapes of a bridge pier
Autorzy:
Muhsen, Noor A.A.
Khassaf, Saleh I.
Powiązania:
https://bibliotekanauki.pl/articles/2174307.pdf
Data publikacji:
2022
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
local scour
pier shape
scour interference
spacing effect
vertical wall abutment
Opis:
Although the complexities and irrevocable consequences associated with bridge scour have attracted researchers interest, their studies scarcely indicated the effect of a bridge pier proximity to an abutment. This research aims to measure maximum scour depth and exhibit the impact of pier-abutment scour interference based on laboratory experiments where vertical-wall abutment and two shapes of a pier (oblong and lenticular) were used at three different spacings (23.5, 16.0, 9.0 cm). The results showed an obvious increase in the scour depth ratio when increasing flow intensity, Froude number, and a decreasing flow depth. They also showed that reduced pier-abutment spacing was accompanied by increase in pier scour for both shapes while decrease in abutment scour. The maximum scour depth that caused by an oblong shape was more than a lenticular shape by about 10.8%. Furthermore, new empirical equations were derived using IBM SPSS Statistics 21 with determination coefficients of 0.969, 0.974, and 0.978 for oblong, lenticular and abutment, respectively. They showed the correlation between predicted and observed data.
Źródło:
Journal of Water and Land Development; 2022, 55; 240--250
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the erosion due to inclined jets
O erozji wywolanej wplywem spod zasuwy
Autorzy:
Minatti, L
Paris, E.
Solari, L.
Powiązania:
https://bibliotekanauki.pl/articles/81751.pdf
Data publikacji:
2010
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
erosion
inclined jet
jet
regime
scour
Opis:
Some preliminary experiments and studies regarding scour processes on a mobile bed caused by inclined jets issuing from a sluice gate are presented. Tests with submerged tailwater conditions have been carried out using different fl ow and geometric conditions. The investigated experimental conditions included different jet Froude numbers, inclinations and tailwater conditions. The bed configuration has been measured during the whole scour hole evolution process until the achievement of a dynamic steady state, where sediment motion was still possible even though it did not allow for any persistent change in the scour and ridge shapes anymore. On the basis of the observed sediment motion, two different patterns of fl ow seem to develop under the investigated conditions: one where the main fl ow remains attached to the bottom of the channel and another where it oscillates between the aforementioned configuration and a surface jet. Some relevant parameters have been identified and used to plot graphs showing their correlation and trends.
W referacie przedstawiono wstępne doświadczenia i badania dotyczące procesów wyboju w rozmywalnym podłożu wywołane przez nachylone strumienie wypływające spod zasuwy. Przeprowadzono doświadczenia dla zatopionej wody dolnej dla różnych przepływów i warunków geometrycznych. Badane warunki doświadczalne zawierały różne liczby Frouda strumienia, nachylenia strumienia i warunki wody dolnej. Konfiguracja dna była rejestrowana w czasie całego procesu ewolucji wyboju aż do osiągnięcia dynamicznego stanu ustalonego, gdzie ruch rumowiska był nadal możliwy, mimo że nie wywoływał dalszej stałej zmiany wyboju ani odkładu rumowiska. Na bazie obserwowanego ruchu rumowiska dwa różne układy przepływu mogą się tworzyć w badanych warunkach: jeden – gdy główny strumień pozostaje przyczepiony do dna kanału i inny – gdzie strumień oscyluje między poprzednio wymienionym i strumieniem powierzchniowym. Pewne parametry zostały zidentyfikowane i wykorzystane przy wykonaniu wykresów wykazujących ich korelacje i trendy.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation; 2010, 42, 1; 187-196
0208-5771
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gravity- and Turbulence-Dominated Sediment Motion in the Clear-Water Scour Process at a Vertical-Wall Abutment in Pressurized Flow
Autorzy:
Radice, A.
Ballio, F.
Tran, C. K.
Powiązania:
https://bibliotekanauki.pl/articles/241458.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
abutment scour
sediment kinematics
turbulence
sliding
Opis:
Results on the motion of sediment particles on the bottom of the erosion hole are shown for a clear-water scour experiment with a vertical-wall abutment. The paper presents an investigation of particle kinematics starting from the division of the grain instantaneous movements into two populations, namely the "turbulence-dominated" events (those in which the particle motion is triggered by the turbulent flow field) and the "gravity-dominated" events (those in which the particles slide along the slopes of the scour hole due to geotechnical instability). Attention is focused on the well developed stages of the erosion process. For such experimental times, the action of the principal vortex system is particularly evident because the latter is not much stretched along the direction of the mean flow deviation, thanks to the increased flowing area. At the same time, the temporal unsteadiness of the vortices lets a bimodal behaviour of the sediments to emerge. A relevant difference has been found between the dynamics of gravity-dominated and turbulence-dominated events. In addition, it was found that the presence of geotechnical effects in the erosion hole may significantly alter the scour rate. Potential implications of the present results for the modelling of local scour processes are described.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2010, 57, 1; 43-59
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and numerical investigation of scour downstream contracted spillways
Autorzy:
Nasralla, Tarek H.
Powiązania:
https://bibliotekanauki.pl/articles/2073735.pdf
Data publikacji:
2022
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
buffers
contraction
downstream
Flow-3D
scour
spillway
Opis:
A study of scour downstream of free hydraulic jump in stilling basin of stepped spillways was carried out. This paper employed an experimental study to investigate the stepped spillway with the movable bed material of D50= 3.1 mm. The effect of the contraction ratio of the stepped spillway was highlighted. Different downstream divergent angle was studied to minimise the scour depth, the results showed that the relative scour depth was reduced by 23% for divergent angle is equal to 170°, different shapes of buffer in stilling basin were also studied to reduce the scour depth where the considered buffer decrease the relative scour depth up to 84%. This study was simulated by Flow 3D program to analyse the scour hole formed using velocity vectors at the bed. The simulated results well agreed with the measured data.
Źródło:
Journal of Water and Land Development; 2022, 52; 53--59
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An overview of bridge pier construction solutions, including the Indonesian approach
Przegląd rozwiązań konstrukcyjnych kształtu filarów mostowych z uwzględnieniem podejścia indonezyjskiego
Autorzy:
Kiraga, M.
Wicaksono, A.Y.
Powiązania:
https://bibliotekanauki.pl/articles/2083908.pdf
Data publikacji:
2020
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
bridge structure
bridge piers
erosion
local scour
hydrotechnics
Opis:
The paper provides an overview of the shape of the bridge piers, including the Indonesian approach. Universal principles of piers construction are provided, however the construction solutions placed in tropical climate conditions are determined by regional factors, such as considerations of resistance to earthquakes, tsunamis or frequent floods. The exemplary shapes of the pillars in the plan and the ways of their foundation are presented as a result of the analysis of English, Polish and Indonesian language literature. The economic role of bridge is emphasized in the context of Indonesian archipelago, where it constitute a central component of transportation system. The damage to the bridge is becoming particularly severe for the economy of the Indonesian archipelago. Therefore other climate invoke different engineerig problems. Structural solutions, which in a way respond to adverse climatic conditions are mainly using proper reinforcement in the case of piers, the drainage systems with a higher drainage capacity and metal components anti-corrosion treatment. Factors that should be considered in the design of the bridge pier shape, size, and configuration could be variously grouped and presented. From this study, following criteria can be distinguished: stability, location, seismic load, stream pressure, aesthetic, collision risk.
Źródło:
Acta Scientiarum Polonorum. Architectura; 2020, 19, 2; 3-20
1644-0633
Pojawia się w:
Acta Scientiarum Polonorum. Architectura
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Artificial Neural Network for Estimation of Local Scour Depth Around Bridge Piers
Autorzy:
Shakir Ali Ali, Ahmed
Günal, Mustafa
Powiązania:
https://bibliotekanauki.pl/articles/2097766.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
artificial neural network
bridge pier
hydraulics
local scour
Opis:
Local scour around bridge piers impairs the stability of bridges’ structures. Therefore, a delicate estimation of the local scour depth is vital in designing the bridge piers foundations. In this research, MATLAB software was used to train artificial neural network (ANN) models with four hundred laboratory datasets from different laboratory studies, including five parameters: pier diameter, flow depth flow velocity, critical sediment velocity, sediment particle size, and equilibrium local scour depth. The outcomes present that the ANN model with the Levenberg-Marquardt algorithm and 11 nodes in the single hidden layer gives an accurate estimation better than other ANN models trained with different training algorithms based on the regression results and mean squared error values. Besides, the ANN model accurately provides predicted local scour depth and is better than linear and nonlinear regression models. Furthermore, sensitivity analysis shows that removing pier diameter from training parameters diminishes the reliability of prediction.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2021, 68, 2; 87--101
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigation of local scour under two oblong piers of a bridge crossing a sharp bend river
Autorzy:
Abdulwahd, Abdulrazaq K.
Maatooq, Jaafar S.
Powiązania:
https://bibliotekanauki.pl/articles/28411623.pdf
Data publikacji:
2023
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
flow intensity
local scour
oblong pier
sharp bend
Opis:
Bridges built across a river bend and supported by more than one pier has been experimentally studied regarding the shape and nature of erosion and deposition. For this purpose, a U-shaped laboratory channel was used with two oblong piers installed at different locations. The first one was at the mid-section of the upstream straight reach, whereas in the second site within the bend, the piers have been installed at sections of central angles 0°, 30°, 60°, 90°, 120°, 150°, 170°, and 180°, from the beginning to the end of the bend segment respectively. The studies were conducted under clear water and threshold flow conditions. The results show that the higher and lower values of local scour around the pier positioned close to the outer bank, are 1.803 and 0.623 times the pier width when the bridge was installed at an angle of 90° and 30° respectively. As for the pier close to the inner bank, the deepest local scour was 1.786 times of the pier width when the bridge was installed at 60° of the bend, while the least one was 0.516 times of the pier width when the bridge was located in the 180° sector. It is worth noting that the presence of piers within sector 150 is less affected by local scour than in the other sections.
Źródło:
Journal of Water and Land Development; 2023, 58; 129--135
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Flow-Altering Countermeasures for Scour at Vertical-Wall Abutment
Autorzy:
Radice, A.
Lauva, O.
Powiązania:
https://bibliotekanauki.pl/articles/241252.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
local scour
abutment
process dynamics
flow-altering countermeasures
sediment transport
Opis:
Results are presented for clear-water scour experiments at a vertical-wall abutment where the obstacle was modified with slots or roughening elements as flow-altering countermeasures against the erosion process. The laboratory campaign comprehended an initial experiment with an unprotected obstacle, two experiments with slots above and beneath the non-scoured bed level, respectively, and one experiment with a roughened abutment. The repeatability of the experiments was checked and found satisfactory. The measured data set consisted of (i) scour depth with time; (ii) geometry of the erosion hole; and (iii) sediment motion pattern at several evolution stages of the process. A novel feature of the work was the attempt to combine evidence on the scour depth and that on sediment motion so as to shed light on the mechanism of scour reduction by the countermeasures tested. It is argued that this strategy might furnish guidelines for future extensive investigations of scour countermeasures, aimed at finding optimal design solutions.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2012, 59, 3-4; 137-153
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study the local scour around different shapes of single submerged groyne
Autorzy:
Rashak, Budoor M.
Khassaf, Saleh I.
Powiązania:
https://bibliotekanauki.pl/articles/1844415.pdf
Data publikacji:
2020
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
bed materials
bed topography pattern
local scour
single submerged groyne
Opis:
River training structures; such as submerged groynes are low profile linear structures that are generally located on the outside bank to form groynes fields and prevent the erosion of stream banks by keeping a flow away from it. In the present research, the maximum scour depth was measured based on laboratory experiments where different shapes of submerged groynes (I-shape, L-shape, T-shape) were used as sort of countermeasures to investigate about most shapes that reduce the scour around them. The result of submerged groynes showed a clear decrease in scour depth ratio due to increasing submerged ratio and increase the scour hole geometry with increasing of flow intensity, and also Froude number. The maximum scour hole in this research was observed at T-shape groyne and then followed by I-shape groyne and L-shape groyne. The maximum scour depth that cased by I-shape was more than L-shape by a percentage about 8.2%, and it was less than T-shape by a percentage about 16.4%.
Źródło:
Journal of Water and Land Development; 2020, 47; 1-9
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Engineering forecasting of the local scour around the circular bridge pier on the basis of experiments
Inżynierskie prognozowanie rozmyć miejscowych wokół walcowego filara mostowego na podstawie doświadczeń
Autorzy:
Bajkowski, Sławomir
Kiraga, Marta
Urbański, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/1852299.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
filar
most
rozmycie
prognoza
badania modelowe
bridge
pier
scour
forecast
model calculations
Opis:
The aim of the study was to indicate the procedure of using laboratory physical model tests of scour around bridge piers for the purposes of determining the potential scour of a riverbed on field bridge crossings. The determination of the uniform modeling scale coefficient according to the criterion of reliable sediment diameter limits the application of the results of tests on physical models to selected types of sediment. The projected depths of scouring of the riverbed at the pier in nature were determined for an object reproduced in the scale of 1:15 determined from the relationship of flow resistance, expressed by hydraulic losses described by the Chézy velocity coefficient, the value of which, in the model and in nature, should be the same. Expressing the value of the Chézy velocity coefficient with the Manning roughness coefficient and introducing the Strickler parameter, it was shown that the coarse sand used in the laboratory bed models the flow resistance corresponding to the resistance generated by gravel in nature. The verification of the calculated size of scouring was based on popular formulas from Russian literature by Begam and Volčenkov [16], Laursen and Toch’s [20] from the English, and use in Poland according to the Regulation ... (Journal of Laws of 2000, No. 63, item 735) [32].
Celem pracy było wskazanie procedury wykorzystania laboratoryjnych fizycznych badań modelowych rozmyć wokół filarów mostowych dla potrzeb określenia potencjalnego rozmycia koryta rzecznego na terenowych przeprawach mostowych. Wykorzystanie wyników badań laboratoryjnych w prognozowaniu rozmyć wokół filarów nowo projektowanych mostów wymaga uwzględnienia wpływu skali modelu. W warunkach analizowanego zadania skalę modelu ustalono z relacji parametrów granulometrycznych rumowiska wykorzystanego w badaniach modelowych i rumowiska rzecznego w cieku, dla którego prowadzono prognozę rozmyć. Określenie współczynnika nieskażonej skali modelowania według kryterium miarodajnej średnicy rumowiska ogranicza zastosowanie wyników badań na modelach fizycznych do wybranych rodzajów rumowiska rzecznego. Prognozowane głębokości rozmycia dna przy filarze w naturze zostały określone dla obiektu modelowanego w skali 1:15 ustalonej z relacji oporów przepływu, wyrażonych stratami hydraulicznymi opisanymi współczynnikiem prędkości Chezy, którego wartość na modelu i w naturze powinna być taka sama. Wyrażając wartość współczynnika prędkości Chezy, współczynnikiem szorstkości Manninga i wprowadzając parametr Stricklera, wykazano, że piasek gruby zastosowany w korycie laboratoryjnym modeluje opory przepływu odpowiadające oporom jakie generuje żwir w naturze. Do weryfikacji obliczonych wielkości rozmyć wykorzystano popularne wśród projektantów formuły z literatury rosyjskiej Begama i Volčenkova [35], angielskiej Laursena i Tocha [36] oraz zalecane do stosowania w Polsce według Rozporządzenia… [5]. W rezultacie otrzymano wzory opisujące wielkości rozmyć dla badanego obiektu ze wskazaniem zakresów ich stosowania.
Źródło:
Archives of Civil Engineering; 2021, 67, 3; 469-488
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Local scour in non-uniform bed material below a horizontal solid apron
Autorzy:
Zawadzki, P.
Błażejewski, R.
Powiązania:
https://bibliotekanauki.pl/articles/240972.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
two-dimensional mathematical model
local scour
horizontal solid
non-uniform bed material
Opis:
A two-dimensional mathematical model of local scour in non-uniform non-cohesive soil below a horizontal solid apron is presented. The model parameters were identified on the basis of own experimental laboratory data. Verification of the model, accomplished using other laboratory data, showed fairly good conformity, however, additional verification under field conditions is needed.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2001, 48, 1; 3-17
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Impact of Bridges on the Process of Water Turbidity on the Example of Large Lowland Rivers
Autorzy:
Szatten, Dawid
Habel, Michał
Babiński, Zygmunt
Obodovskyi, Oleksandr
Powiązania:
https://bibliotekanauki.pl/articles/125164.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
water turbidity
bridge
lower Vistula river
Sukhona river
suspended sediment continuum
contraction scour
Opis:
The transformations of river channels as a result of human activity may reflect the level of anthropogenic pressure. Recorded in macroscale, they are indicators of transformations for the larger part of the river basin, while in the microscale they usually refer to its fragment. The human activity that has the strongest influence on the fluvial processes, including suspended sediment transport, is the interference in the riverbed, such as hydrotechnical construction (create of water stages) or transformation of the river banks (concreting of the river banks). The aim of the research was to determine the impact of bridges on the process of water turbidity in the longitudinal profile of large lowland rivers. The research area was the lower reach of Vistula – bridge profiles: Torun, Bydgoszcz, Kiezmark (Poland) and bridge profile on Sukhona – a tributary of the Northern Dvina River near the city of Veliky Ustyug (Russia – Arkhangelsk Oblast). The research conducted in the years 2013–2017 included the measurements of water turbidity in the cross-sections of the above-mentioned rivers. The determinations of water turbidity were carried out using traditional (granulometry analysis) and nephelometric methods (devices: LISST-25X and turbidimeter). The impact of bridges on the variability of water turbidity was determined. The obtained results were related to the variability of depth conditions (bathymetric measurements) and hydrodynamics in the cross-section profile of the channel.
Źródło:
Journal of Ecological Engineering; 2019, 20, 10; 155-164
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of sandy clay bed material to local scour behaviour
Wpływ piaszczysto-gliniastego materiału podłoża na lokalne rozmycie koryta
Autorzy:
Rustiati, N. B.
Dermawan, V.
Rispiningtati, R.
Limantara, L. M.
Powiązania:
https://bibliotekanauki.pl/articles/947007.pdf
Data publikacji:
2017
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
sandy clay bed material
scour depth
sluice gate
głębokość rozmycia
piaszczysto-gliniasty materiał podłoża
wrota śluzy
Opis:
As a type of gate that is used to control the water level upstream, sluice gate is the gate with simple shape and outstanding ability to flush the sediment. The operation of the gate is considered an important process. The up and down movement of the gate would affect the velocity and cause local scour as the result of fluctuating rate. This research aims to assess the effects of discharge and gate-opening height variations, as well as the type of bedchannel material, on the change of depth of scour (ds). The research was conducted of open channel flow model with a sluice gate able to up and down movement. The discharges used in the research were 9 types ranging from 1.0 to 5.0 dm3·s–1. There were 5 variations in the height of gate-opening ranging from 0.5 to 2.5 cm at intervals of 0.5 and types of channel-bed material. The results of the research showed that the depth of scour can be analysed as a function of discharge, height of gate-opening, height of water level upstream and downstream, and the type of bed material used. The scour depth equation is ds=1.7822(Q/a )1.1347 a. Calculated coefficient of determination of the relationship between two types of channel-bed material and the depth of scour was R2 = 0.946. Consequently, it can be concluded that the equation can be applied on both types of bed-channel material.
Wrota śluzy o prostym kształcie i wyjątkowej zdolności do przemywania osadu są urządzeniem do kontrolowania poziomu wody powyżej śluzy. Ważnym procesem jest sposób operowania wrotami. Ruch wrót w górę i w dół wpływa na szybkość przepływu i powoduje lokalne rozmycie dna. W badaniach prezentowanych w niniejszej pracy oceniano efekt odpływu i zmiennej wysokości otwarcia wrót oraz typu materiału podłoża na głębokość rozmycia (ds). Badania prowadzono na modelowym, otwartym kanale przepływowym z wrotami śluzy o ruchu pionowym. Zastosowano 9 prędkości przepływu – od 1,0 do 5,0 dm3·s–1 i 5 wysokości otwarcia śluzy – od 0,5 do 2,5 cm w przedziałach co 0,5 cm oraz różne typy materiału podłoża. Wyniki badań dowiodły, że głębokość rozmycia można analizować jako funkcję odpływu, wysokości otwarcia śluzy, wysokości poziomu wody powyżej i poniżej śluzy oraz typu użytego podłoża. Otrzymane równanie głębokości rozmycia ma postać ds=1,7822(Q/a )1,1347a . Obliczony współczynnik determinacji dla zależności głębokości rozmycia od dwóch typów materiału podłoża wynosił R2 = 0,946. Można zatem wnioskować, że równanie może być stosowane do obydwu typów podłoża.
Źródło:
Journal of Water and Land Development; 2017, 35; 193-202
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigation for the local scour around V-shaped spur-dikes
Autorzy:
Alasadi, Layth Abdul Rasool
Khlif, Tagreed Hameed
Hassan, Fadhel Abdulabbas
Powiązania:
https://bibliotekanauki.pl/articles/36062042.pdf
Data publikacji:
2023
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
local scour
clearwater conditions
V-shaped spur-dyke
checkmark spur-dyke
river training structure
sediment transport
Opis:
Spur-dikes are efficient hydraulic structures that are made for numerous purposes. They have one end on the stream bank and another extending into the current. As a result of the existing spur-dikes in the stream course, the local scour phenomena usually occur around them, leading to several predicaments which have been of great concern to the hydraulic engineers. For the present work, laboratory experiments were carried out to measure the scour depths around several spur-dikes located at different distances for the V-shaped one. The experiments were conducted using physical models installed in a non-curved flume with a bed with uniform cohesion-less sediment of a medium particle size (d50 = 0.7 mm). All the models were operated under the subcritical flow of clear-water conditions. The investigations include three spur-dikes (1, 2 and 3) and three distances between them (1, 1.5 and 2 of spur-dike length) as two countermeasures to minimize the local scour depths. The results showed that an increasing number of spur-dikes and the distances between them would decrease the scour depths within the limit of the present study. The experimental data were used to create a new formula of R = 0.954 that reflects a good agreement with the experimentally observed results.
Źródło:
Scientific Review Engineering and Environmental Sciences; 2023, 32, 1; 68-86
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
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