Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "sand model" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-13 z 13
    Tytuł:
    Technical Note: Liquefaction mechanism induced by dynamic excitation modeled in Plaxis AE with the use of UBC and Mohr–Coulomb constitutive relationships
    Autorzy:
    Borowiec, A.
    Stanuszek, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/178355.pdf
    Data publikacji:
    2016
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    liquefaction
    constitutive relationships
    UBC Sand model
    Mohr-Coulomb model
    numerical modeling in Plaxis
    Opis:
    Computer Aided Engineering (CAE) is commonly used in modern design of the various types of structures. There are two main issues/aspects that should be consider while using CAE in Geotechnics: the basic theory and material model. The paper deals with a problem of choosing the proper constitutive relationships which according to the authors are equally important in obtaining correct and reasonable results. This problem is illustrated by an example of dynamic calculations of fully saturated non-cohesive soils where liquefaction phenomenon is most likely to occur.
    Źródło:
    Studia Geotechnica et Mechanica; 2016, 38, 1; 123-133
    0137-6365
    2083-831X
    Pojawia się w:
    Studia Geotechnica et Mechanica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Cam-clay approach to modelling pre-failure behaviour of sand against experimental data
    Autorzy:
    Sawicki, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/240978.pdf
    Data publikacji:
    2003
    Wydawca:
    Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
    Tematy:
    pre-failure deformations of sand
    elastic-plastic model of sand
    Cam-Clay type
    Opis:
    The aim of this paper is to compare pre-failure deformations of sand, obtained from a Cam-clay type elastic-plastic model, with experimental data. The experiments were performed in a modern triaxial apparatus, enabling local measurement of both vertical and lateral strains. The experimental programme is briefly described, then a slightly modified, Cam-clay type, elastic-plastic model of sand is presented. Predictions of this model, for different stress paths, are compared with respective experimental results, then extensive discussion of basic problems connected with elasto-plastic modelling of sand is presented. The aim of the discussion is to display some shortcomings of this type of modelling.
    Źródło:
    Archives of Hydro-Engineering and Environmental Mechanics; 2003, 50, 3; 229-249
    1231-3726
    Pojawia się w:
    Archives of Hydro-Engineering and Environmental Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Express techniques for laboratory definition of reservoir permeability recovery coefficient due to the influence of fracturing fluid
    Szybkie techniki do określenia laboratoryjnego współczynnika odzysku przepuszczalności zbiornika ze względu na oddziaływanie płynu szczelinującego
    Autorzy:
    Gubanov, V. B.
    Malkin, D. N.
    Magadova, L. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1835434.pdf
    Data publikacji:
    2017
    Wydawca:
    Instytut Nafty i Gazu - Państwowy Instytut Badawczy
    Tematy:
    cross-linked polysaccharide gel
    destruction
    fluid
    filtration
    fracture
    guar
    per-meability
    porosity
    proppant
    sand model
    sieciowany polisacharydowy żel
    destrukcja
    płyn
    filtracja
    szczelina
    przepuszczalność
    porowatość
    propant
    model piaskowy
    Opis:
    An express method of fracturing fluid influence estimation on the permeability of production reservoirs is offered, by using a sandpack model heated up to reservoir temperature. A part of the model is filled with quartz sand fraction of a given permeability. The rest of the model is filled with proppant. The model is saturated with saline water and heated up to reservoir temperature. Initially, water permeability for the sand-pack model part is determined. Then, hydraulic fracturing fluid is injected in the model proppant part. During injection, recording of the filtrate volume and differential pressure changing, allows us to estimate the filterability of the fracturing fluid. After exposure time for fluid breaking, during the filtration process of saline water in the opposite direction, we can estimate destruction rate according to the obtained permeability recovery coefficient of the model part filled with sand. In this article the results of the plugging properties investigation and the impact on permeability of the porous medium before and after the gel destruction of the two fracturing fluids (cross-linked polysaccharide gel and the experimental non-guar of fracturing fluid) are shown. There are significant differences in fluid behavior during filtration through a porous medium, which depends on the mechanisms of gel systems formation. It is shown, that the recovery factor of permeability, depends on the depth of fracturing fluid penetration in a porous medium.
    Szybka metoda oszacowania wpływu płynu szczelinującego na przepuszczalność zbiornika produkcyjnego jest oferowana poprzez zastosowanie modelu sand-pack podgrzanego do temperatury zbiornika. Część tego modelu jest wypełniona frakcją piasku kwarcowego o określonej przepuszczalności. Reszta modelu jest wypełniona podsadzką. Model ten jest nasycony solanką i ogrzany do temperatury zbiornika. Początkowo, przepuszczalność wody części modelu sand-pack jest ustalona. Następnie, płyn do szczelinowania hydraulicznego jest wtryskiwany do części modelu podsadzki. Podczas wtrysku, zapis zmiany objętości filtratu i ciśnienia różnicowego pozwala na oszacowanie filtrowalności płynu szczelinującego. Po czasie ekspozycji na zerwania płynu w trakcie procesu filtracji słonej wody w przeciwnym kierunku, można oszacować wskaźnik zniszczenia, w zależności otrzymanego współczynnika odzysku przepuszczalności tej części modelu wypełnionej piaskiem. W artykule są pokazane wyniki badania właściwości zatykania oraz wpływu na przepuszczalność porowatego nośnika przed i po zniszczeniu żelu dwóch płynów szczelinujących (usieciowanego żelu polisacharydu i eksperymentalnego non-guar płynu szczelinującego). Istnieją znaczące różnice w zachowaniu płynu podczas filtracji przez porowaty nośnik, które zależą od mechanizmów powstawania systemów żelowych. Jak widać, współczynnik odzyskiwania przepuszczalności zależy od głębokości penetracji płynu szczelinującego w porowatym nośniku.
    Źródło:
    Nafta-Gaz; 2017, 73, 4; 236-241
    0867-8871
    Pojawia się w:
    Nafta-Gaz
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Model tests on characteristic of suction caissons in saturated fine sand under intermittent loading
    Autorzy:
    Shi, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/258534.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
    Tematy:
    intermittent suction installation
    model test
    sand
    suction caisson
    Opis:
    Suction caissons are often used for the caissons of both offshore oil platforms and offshore wind power projects because of their advantages of simple construction, economical cost, and reusability. In this study, model tests were conducted in sand in order to investigate the effects of the caisson installation method on the penetration depth and the critical suction. Results of the test program showed that the method of changing the frequency of suction during different stages of the process can increase the penetration depth of the caisson. Combining with the deformation of the soil body inside and outside the caisson, the existing method for calculating the critical suction is modified, and the critical suction calculation equation of the discontinuous penetration test is proposed. Based on the test results, the calculation equation of the soil heave height can be more accurate predicted. The analysis results verify that the calculation method and the actual results are in good agreement.
    Źródło:
    Polish Maritime Research; 2018, S 3; 127-135
    1233-2585
    Pojawia się w:
    Polish Maritime Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical Simulations of Triaxial Test with Sand Using DEM
    Autorzy:
    Widuliński, Ł.
    Kozicki, J.
    Tejchman, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/241337.pdf
    Data publikacji:
    2009
    Wydawca:
    Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
    Tematy:
    discrete element model
    rolling resistance
    sand
    triaxial test
    Opis:
    Numerical simulations of the behaviour of cohesionless sand were carried out using a discrete element method. A drained triaxial test of a homogeneous sand specimen under constant lateral pressure was modelled. To simulate the behaviour of sand, a 3D spherical discrete model YADE was used, enhanced by including rolling resistance in order to take into account grain roughness. Numerical results were directly compared with corresponding laboratory tests. The effects of lateral pressure, initial void ratio and micro-parameters on the global behaviour of sand were investigated.
    Źródło:
    Archives of Hydro-Engineering and Environmental Mechanics; 2009, 56, 3-4; 149-172
    1231-3726
    Pojawia się w:
    Archives of Hydro-Engineering and Environmental Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study of the curative role of "Draas" in evacuating dunes threatening roads in the Lower Algerian Sahara: physical model on a smaller scale
    Autorzy:
    Sebaa, A. K.
    Belhamra, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/231183.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sieć dróg
    piasek dryfujący
    ściana przeciwpiaskowa
    osłona przeciwpiaskowa
    model zredukowany
    Sahara Algierska Dolna
    road network
    sand drifting
    anti-sand wall
    reduced model
    Lower Algerian Sahara
    Opis:
    Sand drifting on road networks in the region of the Lower Algerian Sahara is one of the main problems for the sector. Machines are repeatedly deployed to overcome this phenomenon. The long experience acquired while dealing with the removal of sand from roads pushed us to focus on obstacles called "Draas". The purpose of this study is to perform an optimization of these special protective structures called “Draas”, using a reduced physical model. Model tests were performed in flow channel. The principle of modeling the wind transport using a reduced model is to simulate the wind using a liquid stream while respecting the laws of hydraulic and sedimentological similarity. The results obtained are extrapolated to make a normal size prototype.
    Źródło:
    Archives of Civil Engineering; 2018, 64, 4/I; 15-35
    1230-2945
    Pojawia się w:
    Archives of Civil Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Proposal of concept for structural modelling of hybrid beams
    Autorzy:
    Kożuch, Maciej
    Skrętkowicz, Łukasz
    Powiązania:
    https://bibliotekanauki.pl/articles/2172884.pdf
    Data publikacji:
    2022
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    sand
    mean grain size
    mean pore size model
    pore size distribution
    water retention curve
    Opis:
    Investigation on the behaviour of a hybrid beam is presented. Hybrid beam stands for an element with hybrid cross sections. This means sections that consist of steel and concrete parts, connected together with composite dowels, and both are considered for shear flow analysis. In practice, a more general solution may be used for bridges in the form of a beam in which the span sections are hybrid and the support sections are concrete. Recently such a solution has been introduced for bridge engineering in Poland and a new problem with performing a global analysis of hybrid beams was identified. The solution is new itself and requires also a new approach for internal forces determination. Discussion of this problem is made in the paper. Influences of (1) concrete cracking, (2) rheology of concrete and (3) methods of modelling on the redistribution of internal forces are highlighted. On an example of one of the real bridge girder (being currently under design) analysis is made to show how the abovementioned factors are affecting obtained results. Results are analysed and conclusions are presented. As a final step, a new concept of hybrid beam design is proposed. The proposed solution enables a quick and easy engineering approach to perform a static calculation of the considered structure.
    Źródło:
    Studia Geotechnica et Mechanica; 2022, 44, 4; 317--332
    0137-6365
    2083-831X
    Pojawia się w:
    Studia Geotechnica et Mechanica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The golf-ball model and the purpose of drumlin formation
    Autorzy:
    Smalley, Ian J.
    Lu, Ping
    Jefferson, Ian F.
    Powiązania:
    https://bibliotekanauki.pl/articles/2026748.pdf
    Data publikacji:
    2000
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Drumlin formation
    sub-glacial deforming layer
    golf-ball model
    self-organisation
    sand heap analogy
    Turinginstability
    Opis:
    The purpose of drumlin formation is to facilitate glacier flow. Drumlins form in a deforming layer between ice and s q ground, they produce a pimpled ground surface which causes less drag in the flowing system, after the fashion of the Prandtl effect which reduces boundary layer detachment (as in the flying golf ball). This pimpled surface has selforganising properties and this causes the development of a low drag situation. The drumlin field is the critical phenomenon; the formation of individual drumlins is a small part of the overall effect.
    Źródło:
    Studia Quaternaria; 2000, 17; 29-33
    1641-5558
    2300-0384
    Pojawia się w:
    Studia Quaternaria
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Field validation of DNDC and SWAP models for temperature and water content of loamy and sandy loam Spodosols
    Autorzy:
    Balashov, E.
    Buchkina, N.
    Rizhiya, E.
    Farkas, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/972349.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Tematy:
    field validation
    agroecosystem
    modelling
    soil water content
    soil temperature
    DNDC model
    SWAP model
    temperature
    water content
    loamy sand
    sandy loam
    Spodosol
    Opis:
    The objectives of the research were to: fulfil the preliminary assessment of the sensitivity of the soil, water, atmosphere, and plant and denitrification and decomposition models to variations of climate variables based on the existing soil database; validate the soil, water, atmosphere, and plant and denitrification and decomposition modelled outcomes against measured records for soil temperature and water content. The statistical analyses were conducted by the sensitivity analysis, Nash-Sutcliffe efficiency coefficients and root mean square error using measured and modelled variables during three growing seasons. Results of sensitivity analysis demonstrated that: soil temperatures predicted by the soil, water, atmosphere, and plant model showed a more reliable sensitivity to the variations of input air temperatures; soil water content predicted by the denitrification and decomposition model had a better reliability in the sensitivity to daily precipitation changes. The root mean square errors and Nash-Sutcliffe efficiency coefficients demonstrated that: the soil, water, atmosphere, and plant model had a better efficiency in predicting seasonal dynamics of soil temperatures than the denitrification and decomposition model; and among two studied models, the denitrification and decomposition model showed a better capability in predicting the seasonal dynamics of soil water content.
    Źródło:
    International Agrophysics; 2014, 28, 2
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An analytical model to predict water retention curves for granular materials using the grain-size distribution curve
    Autorzy:
    Bouacida, Linda
    Feia, Sadok
    Denine, Sid Ali
    Della, Noureddine
    Powiązania:
    https://bibliotekanauki.pl/articles/2172891.pdf
    Data publikacji:
    2022
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    sand
    mean grain size
    mean pore size
    density index
    model
    pore size distribution
    water retention curve
    Opis:
    The present work aims to propose a new analytical model intended to predict the water retention curves for granular materials based on data from tensiometric tests. Different analytical models have been used for the evaluation of soil water retention curves so far. It should be noted that the proposed model considers only one criterion in the selection of soils. This criterion is the physical property of particle distribution curve that can be used to determine the values of D50 and CU. In this study, the pore-access size distribution is investigated considering the effect of the coefficient of uniformity of sandy soils that were prepared with different density indexes (0.5, 0.7, and 0.9). Moreover, the proposed model equation is based on the physical properties of soil. This equation made it possible to describe the water retention curve and to estimate the pore-access size distribution without performing any experimental tests. The findings allowed asserting that the uniformity of the particle size curves corresponds to a good uniformity of the pore-access size distribution. In addition, it was revealed that the suction increased as the density index went up, which matches well with the experimental data. Moreover, it may clearly be noted that the distinctive retention properties of unsaturated soils can be observed on the above-mentioned curves. Further, it was found that the ratio of the grain size over the pore-access size increased as the uniformity coefficient augmented.
    Źródło:
    Studia Geotechnica et Mechanica; 2022, 44, 4; 354--369
    0137-6365
    2083-831X
    Pojawia się w:
    Studia Geotechnica et Mechanica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Seismic damage behaviour of aeolian sand reinforced concrete columns with I-shaped structural steel
    Autorzy:
    Wang, Y. H.
    Wang, H. Y.
    Wang, Y. P.
    Zhao, M.
    Qi, J.
    Huo, G. Z.
    Liu, P. Q.
    Powiązania:
    https://bibliotekanauki.pl/articles/1849772.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    piasek eoliczny
    słup żelbetowy
    stal konstrukcyjna
    przekrój I
    zachowanie
    uszkodzenie sejsmiczne
    model uszkodzenia
    aeolian sand
    column
    I-shaped steel
    structural steel
    seismic damage
    behaviour
    damage model
    Opis:
    To promote the application of aeolian sand resources for steel-concrete composite structures, an aeolian sand reinforced concrete column with I-shaped structural steel is proposed in this study. Four specimens are designed and manufactured with different replacement rates of aeolian sand. The seismic behaviour and damage evolution process of the specimens are studied by low-cycle repeated loading tests. Based on the test results, the mechanical characteristics, failure modes, hysteresis curves, skeleton curves, energy dissipation capacity, displacement ductility, and stiffness degradation of the specimens with different replacement rates of aeolian sand are analysed. In addition, the effects of the design parameters on the seismic behaviour of the specimens are also studied. The results show that the indexes of the seismic behaviour can be significantly improved by adding steel. Moreover, a revised damage model is proposed, to better reflect the evolution law of seismic damage of aeolian sand reinforced concrete columns with steel. The proposed model can provide an important reference for seismic damage assessment of the columns.
    Źródło:
    Archives of Civil Engineering; 2020, 66, 4; 633-650
    1230-2945
    Pojawia się w:
    Archives of Civil Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Innovative Foundry Technology and Material Using Fused Deposition Modeling and Polylactic Acid Material in Sand Casting
    Autorzy:
    Anakhu, P. I.
    Bolu, C. C.
    Abioye, A. A.
    Onyiagha, G.
    Boyo, H.
    Jolayemi, K.
    Azeta, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/381692.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    fused deposition modeling
    rapid pattern
    sand casting pattern
    FDM printed
    PLA pattern
    mold cavity
    osadzanie przetopionego materiału
    model odlewniczy
    gniazdo formujące
    Opis:
    In sand casting, Fused Deposition Modeling (FDM) printing by using Poly Lactic Acid (PLA) filament is one of the innovative foundry technologies being adopted to substitute traditional pattern making. Several literatures have reported the influence of process parameters such as raster angle and print speed on some mechanical properties of FDM-printed, PLA-prototypes used in other applications. This study investigated the effects of interior fill, top solid layer, and layer height on the compressive strength of rapid patterns for sand casting application. Different values of the process parameters were used to print the pre-defined samples of the PLA-specimens and a compression test was performed on them. The coupled effects of the process parameters on compressive strength were investigated and the optimum values were determined. Interior fill of 36%, layer height of 0.21 mm and top solid layer of 4 were found to produce a FDM-printed, PLA-pattern that sustained a compaction pressure of 0.61 MPa. A simulation analysis with ANSYS® to compare failure modes of both experiment and model shows a similarity of buckling failure that occurred close to the base of each specimen.
    Źródło:
    Archives of Foundry Engineering; 2018, 18, 2; 65-71
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Prediction of bearing capacity of H shaped skirted footings on sand using soft computing techniques
    Autorzy:
    Gnananandarao, -
    Khatri, V. N.
    Dutta, R. K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1818514.pdf
    Data publikacji:
    2020
    Wydawca:
    Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
    Tematy:
    bearing capacity ratio
    sand
    artificial neural networks
    M5P model tree
    regular plan shaped skirted footings
    H plan shaped skirted footings
    współczynnik nośności
    piasek
    sztuczne sieci neuronowe
    drzewo modelu M5P
    Opis:
    Purpose: The present study aims to apply soft computing techniques, Artificial Neural Network (ANN) and M5P model tree, to predict the ultimate bearing capacity of the H plan shaped skirted footing on the sand Design/methodology/approach: A total of 162 laboratory test data for the regular plan shaped (square, circular, rectangular, and strip (up to L/B = 2.5) skirted footing were collected from the literature to develop the soft computing-based models. These models were later modified for the H Plan shaped skirted footing with the introduction of the multiplication factor. The input variables chosen for the regular plan shaped footings were skirt depth to width of the footing ratio (Ds/B), friction angle of the sand (o), the ratio of the interface friction angle-to-friction angle of sand (5/o), and length-to-width (L/B) ratio of the footing. The output is the bearing capacity ratio (BCR, a ratio of the bearing capacity of the skirted footing to the bearing capacity of un-skirted footing). Findings: Sensitivity analysis was carried out to see the impact of the individual variable on the BCR). The sensitivity results reveal that the skirt depth to width of the footing ratio is the primary variable affecting the BCR. Finally, the performance of the developed soft computing models was assessed using six statistical parameters. The results from the statistical parameters reveal that model developed using ANN was performing superior to the one prepared using M5P model tree technique for the prediction of the ultimate bearing capacity of H plan shaped skirted footing on sand. Research limitations/implications: The model equations are developed with experimental laboratory data. Hence, these equations need further improvement by using field data. However, until now there no field data have been available to include in the present data set. Practical implications: These proposed model equations can be used to predict the bearing capacity of the H-shaped footing with the help of Ds/B, o, S/o and L/B without performing the laboratory experiments. Originality/value: There is no such model equation that was developed so far for the H-shaped skirted footings. Hence, an attempt was made in this article to predict the bearing capacity of the H-shaped footing by using available experimental data with the help of soft computing techniques.
    Źródło:
    Archives of Materials Science and Engineering; 2020, 103, 2; 62--74
    1897-2764
    Pojawia się w:
    Archives of Materials Science and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-13 z 13

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies