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 "Tejchman, J" wg kryterium: Wszystkie pola

  Lista filtrów
Wyrównaj
Wyświetlanie 1-25 z 38
Tytuł:
Simulation of shear localization in granular bodies within gradient-enhanced hypoplasticity
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241309.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
characteristic length
finite element method
gradient model
plane strain compression
shear localization
Opis:
The paper presents a FE-analysis of a spontaneous shear localization inside non-cohesive sand during plane strain compression. The calculations were carried out with a gradient-enhanced hypoplastic constitutive law. The hypoplastic law can reproduce essential features of granular bodies depending on the void ratio, pressure level and deformation direction. To model the thickness of shear zones, a characteristic length of the microstructure was incorporated via the second gradient of the modulus of the deformation rate. To determine the effect of micro-structure, the analysis was performed with different characteristic lengths for the same specimen size.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2004, 51, 3; 243-265
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Grain Crushing on Shear Localization in Granular Bodies within Micro-Polar Hypoplasticity
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241516.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
breakage mechanics
grain crushing
micro-polar hypoplasticity
sand
shearing
Opis:
The paper deals with the effect of grain crushing on shear localization in granular materials in an infinite long narrow granular strip under constant vertical pressure. The calculations were carried out with an enhanced micro-polar hypoplastic constitutive model which is able to describe the salient properties of crushable granular bodies including shear localization. The change of the mean grain diameter with varying pressure was taken into account with the help of formulae from breakage mechanics. The effect of pressure and initial void ratio on shear localization was studied.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2010, 57, 1; 3-30
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigations of shear localization in granular bodies within an anisotropic micro-polar hypoplasticity
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241368.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
bedding plane
granular materials
hypoplasticity
micropolar theory
shear zone
texturial anisotropy
Opis:
The paper focuses on the numerical analysis of the effect of texturial anisotropy on shear localization in cohesionless granular materials. For simulation of the mechanical behaviour of a granular material during a monotonous deformation path, a hypoplastic constitutive model was used. To take into account a characteristic length of micro-structure, the constitutive model was extended by micro-polar terms. To take into account texturial effects, the granular hardness was modified. The calculations were carried out with a sand specimen during plane strain compression under constant lateral pressure. A stochastic and uniform distribution of the initial void ratio in the granular specimen was assumed. In addition, shear localization for two different uniform initial void ratios was investigated.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2005, 52, 4; 351-371
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Non-local hypoplastic constitutive law to describe shear localisation in granular bodies
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/240962.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
characteristic length
finite element method
non-local model
plane strain compression
shear localization
Opis:
The paper presents a FE-analysis of shear localisation in granular bodies by a finite element method based on a hypoplastic constitutive law. The law can reproduce essential features of granular bodies depending on the void ratio, pressure level and deformation direction. To realistically simulate the formation of a spontaneous shear zone inside cohesionless sand during plane strain compression, a hypoplastic constitutive law was extended by non-local terms. The effects of initial void ratio, pressure level and a characteristic length on the thickness of an interior shear zone were shown. The numerical results were compared with corresponding laboratory tests.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2003, 50, 4; 359-379
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
FE-simulations of rapid silo flow with a polar elasto-plastic constitutive model
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1953957.pdf
Data publikacji:
1998
Wydawca:
Politechnika Gdańska
Tematy:
finite element simulations
polar elasto-plastic constitutive model
silo flow
numerical modelling
model silo
convergent smooth walls
Opis:
The paper presents results on numerical modelling of rapid flow of granular materials in a model silo with convergent smooth walls. The calculations were performed with a finite element method based on a polar elasto-plastic constitutive relation by Muhlhaus (1995). The relation differs from the conventional theory of plasticity by the presence of Cosserat rotations and couple stresses using a mean grain diameter as a characteristic length. The characteristic length causes that numerical results do not depend upon the mesh discretisation. The model tests on rapid silo flow of glass beads performed by Renner in a glass hopper with a large wall inclination from the bottom were numerically simulated. The plane strain FE-calculations were performed by taking into account inertial forces and linear viscous damping. A satisfactory agreement between numerical and experimental results was obtained. Advantages and limitations of a continuum approach for simulations of rapid silo flow were outlined.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 3; 473-501
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical studies on patterning of shear zone in granular bodies
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1954556.pdf
Data publikacji:
2000
Wydawca:
Politechnika Gdańska
Tematy:
localisation
hypoplasticity
polar continuum
boundary conditions
shear zone
finite element method
Opis:
The paper deals with numerical investigations on the patterning of shear zones in granular bodies. The behaviour of dry sand during plane strain compression tests was numerically modelled with a finite element method using a hypoplastic constitutive relation within a polar (Cosserat) continuum. The constitutive relation was obtained through an extension of a non-polar one by polar quantities, viz. rotations, curvatures, couple stresses using the mean grain diameter as a characteristic length. This relation can reproduce the essential features of granular bodies during shear localisation. The material constants can be easily determined from element test results and can be estimated from granulometric properties. The attention is laid on the influence of boundary conditions and the distribution of imperfections in the granular specimen on the formation of patterns of shear zones.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2000, 4, 3; 485-516
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of heterogeneity on shear zone formation during plane strain compression
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241506.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
heterogeneity
mean grain diameter
polar continuum
shear zone
void ratio
Opis:
Heterogeneity of granular materials triggers shear zone formation. In the paper, the FE-analysis of the effect of the material heterogeneity on the formation of a spontaneous shear zone inside of granular materials during a plane strain compression test is presented. The numerical calculations are performed with a finite element method on the basis of a hypoplastic constitutive law extended by polar quantities: rotations, curvatures and couple stresses. A mean grain diameter is used as a characteristic length. The constitutive law takes into account the effect of pressure, void ratio, direction of deformation rate and mean grain diameter on the behaviour of granular bodies. The heterogeneity in the granular body is assumed in the form of spots with a different initial void ratio. The spots are single or distributed randomly and stochastically with an exponential probability function. The single spots are distributed sparsely and densely in an initially dense and loose granular specimen. Special attention is focused on the effect of heterogeneity on the onset of shear localization and its thickness at residual state.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2004, 51, 2; 149-181
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
FE studies of quasi-static mass flow in bins: the polar elasto-plastic approach
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1955765.pdf
Data publikacji:
2003
Wydawca:
Politechnika Gdańska
Tematy:
elasto-plasticity
finite element method
flow
polar approach
silo
Opis:
The paper deals with numerical modelling of confined flow of granular materials in vertical bins. Quasi-static mass flow of non-cohesive sand with a controlled outlet velocity along the entire silo bottom was numerically studied using a finite element method taking into account an elasto-plastic constitutive law laid down within a Cosserat continuum. The influence of the initial density and the mean grain diameter of the solid, wall roughness, wall stiffness and imperfection, the initial stress state and the pressure level on the stress and deformation states in plane-strain vertical bins was investigated. The numerical results were compared with similar model tests performed with a rectangular vertical bin containing sand. The calculated results were in satisfactory agreement with the experimental ones. The advantages and limitations of the polar elasto-plastic approach to model granular silo flow were outlined.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2003, 7, 4; 667-699
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evolution of shear localisation in earth pressure problems of a retaining wall
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1986988.pdf
Data publikacji:
2002
Wydawca:
Politechnika Gdańska
Tematy:
earth pressure
granular materials
finite element method
hypoplasticity
polar continuum
retaining wall
shear localization
Opis:
The paper deals with numerical investigations of the evolution of shear localisation in granular bodies for earth pressure problems of a retaining wall in conditions of plane strain. The passive and active failure of a retaining wall in sand is discussed. The calculations are carried out with a rigid and very rough retaining wall undergoing horizontal translation, rotation around the top and rotation around the bottom. The behaviour of dry sand is numerically modelled with a finite element method using a hypoplastic constitutive relation within a polar (Cosserat) continuum. The constitutive relation is obtained through extension by polar quantities, viz. rotations, curvatures and couple stresses, using the mean grain diameter as a characteristic length. During FE-calculations, the attention is laid on the influence of different wall movements on shear localisation. In addition, the effects of the initial void ratio, distribution of the initial void ratio and mean grain diameter, pressure level and size of the sand body and retaining wall is investigated in the case of a passive wall translation. The FE-results are compared with corresponding experimental results of laboratory model tests.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2002, 6, 3; 387-410
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fe-analysis of patterning of shear zones in granular bodies for earth pressure problems of a retaining wall
Autorzy:
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241166.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
earth pressure
granular materials
finite element method
hypoplasticity
polar continuum
retaining wall
shear localization
Opis:
The evolution of shear zones in granular bodies for earth pressure problems of a retaining wall in conditions of plane strain was analyzed. The passive and active failure of a retaining wall was discussed. The calculations were carried out with a rigid and very rough retaining wall undergoing horizontal translation, rotation around the top and rotation around the bottom. The behaviour of dry sand was numerically modelled with a finite element method using a hypoplastic constitutive relation with polar extensions. Attention was paid to the influence of different wall movements on shear localization. The initial void ratio was assumed to be non-uniformly distributed. The geometry of calculated shear zones was compared with corresponding experimental results of laboratory model tests.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2004, 51, 4; 317-348
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of a cellular automata model to granular flow
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1986936.pdf
Data publikacji:
2002
Wydawca:
Politechnika Gdańska
Tematy:
cellular automata
granular flow
silo
passive state
active state
Opis:
Paper presents the results of simulations of granular flow with a cellular automata model. Flow of granular material behind a moving retaining wall and in a silo with inserts was numerically analysed. Two different migration schemes during flow were assumed. Advantages and limits of the model were outlined.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2002, 6, 3; 429-436
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulations of behaviour of granular bodies using a lattice-gas automaton
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241283.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
collisions
dissipation
granular flow
gravity
lattice-gas automaton
Opis:
A lattice-gas automaton of hydrodynamics was used to calculate the kinematics of non-cohesive granular materials during 3 different complex two-dimensional problems: granular pile, granular flow in a vertical channel and granular flow in a parallel/converging silo. In the model, collisions and dissipation of particles were taken into account. The simulation results were qualitatively compared with experimental results.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2005, 52, 1; 21-37
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
2D Lattice Model for Fracture in Brittle Materials
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241484.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
beam
brittle material
discrete method
fracture
lattice model
size effect
Opis:
The numerical simulations show the potential of a lattice discrete approach to model fracture during brittle materials in different two-dimensional quasi-static processes of loading behaviour. The 2D calculations were carried out for brittle specimens subject to uniaxial compression, uniaxial extension and shear. The effect of the specimen size on the global stress-strain diagram during uniaxial tension was also investigated. The advantages and disadvantages of the model were outlined.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2006, 53, 2; 137-154
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulations of flow patterns in silos with a cellular automaton: Part 1
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1965146.pdf
Data publikacji:
2005
Wydawca:
Politechnika Gdańska
Tematy:
cellular automation
granular flow
flow pattern
insert
silo
Opis:
A simplified cellular automaton was used to calculate the kinematics of non-cohesive granular materials during confined flow in silos. In this model, granular flow was assumed to be an upward propagation of holes through a lattice composed of cells representing single particles. Calculations were carried out with different silo shapes and inserts, transition probabilities, migration rules, outflow schemes, grid types, wall roughness and cell numbers. To visualize the calculation process, horizontal layers of various shades were introduced. The simulation results were compared with laboratory tests in model silos.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2005, 9, 1; 81-102
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of concrete behaviour with a non-local continuum damage approach
Autorzy:
Bobiński, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241347.pdf
Data publikacji:
2005
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
characteristic length
concrete
crack
damage model
FEM
non-local theory
Opis:
The paper presents FE-results on the behaviour of concrete under plane strain conditions. The material was modelled using a simple isotropic damage continuum model. The model was enriched by non-local terms to avoid a pathological mesh-sensitivity and to obtain a well-posed rate boundary value problem. The constitutive model was used to simulate localization of deformation in 3 benchmark problems: a double-edge notched specimen under uniaxial tension and a notched beam under three- and four-point bending. Attention was laid on the effect of a characteristic length on the load-displacement curves and strain localization. The FE-results were compared with experiments and other numerical studies.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2005, 52, 3; 243-263
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Non-local elasto-plastic model to describe localisations of deformation in concrete
Autorzy:
Bobiński, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1986935.pdf
Data publikacji:
2002
Wydawca:
Politechnika Gdańska
Tematy:
concrete
localisation
non-local theory
elasto-plasticity
characteristic length
Opis:
The paper presents numerical simulations of behaviour of concrete elements subjected to uniaxial compression for plane strain. FE-calculations are performed with two different elasto-plastic constitutive laws for concrete. Numerical results obtained suffer from mesh sensivity due to the presence of material softening. To obtain a well-posed boundary problem and a mesh independent solution, conventional constitutive laws with softening require an extension (called regularisation) to describe properly the localisations of deformations. In this paper elasto-plastic constitutive laws are extended by non-local strain terms. Owing to them, localisations of deformations are realistically captured.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2002, 6, 3; 437-446
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulations of flow patterns in silos with a cellular automaton: Part 2
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1965144.pdf
Data publikacji:
2005
Wydawca:
Politechnika Gdańska
Tematy:
cellular automation
collisions
density wave
granular flow
flow pattern
silo
Opis:
An improved cellular automaton has been used to calculate the kinematics of non-cohesive granular materials during confined flow in mass and funnel flow model silos. In this model, based on a gas model of hydrodynamics, collisions and dissipation of particles were taken into account during granular flow. The model allowed for investigations of dilatant zones in granular material during silo flow.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2005, 9, 1; 103-114
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Size Effects in Problems of Footings on Sand within Micro-Polar Hypoplasticity
Autorzy:
Tejchman, J.
Górski, J.
Powiązania:
https://bibliotekanauki.pl/articles/241079.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
footing
micro-polar hypoplasticity
sand
shear localization
size effect
stratified sampling
void ratio
Opis:
Numerical FE investigations of size effects in problems of footings on sand were performed. Micro-polar hypoplastic constitutive model was used to describe a mechanical behaviour of a cohesionless granular material during a monotonic deformation path. The FE analyses were carried out with three different footing widths. In deterministic calculations, a uniform distribution of initial void ratio was used. In statistical calculations, initial void ratios took the form of random spatial fields described by a truncated Gaussian random distribution. In order to reduce the number of stochastic realizations without sacrificing the accuracy of the calculations, a stratified sampling method was applied. The numerical results were compared with corresponding laboratory tests by Tatsuoka et al (1997). The numerical results show that the bearing capacity of footings decreases with increasing specimen size. If the initial void ratio is stochastically distributed, the mean bearing capacity of footings may be larger than the deterministic value. The statistical size effect is smaller than the deterministic one.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2008, 55, 3-4; 95-124
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of behaviour of reinforced concrete elements under eccentric compression
Autorzy:
Majewski, T.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/1986991.pdf
Data publikacji:
2002
Wydawca:
Politechnika Gdańska
Tematy:
eccentric compression
concrete
finite element method
reinforced concrete
reinforcement
Opis:
Paper presents results of numerical modelling of behaviour of plane strain reinforced concrete elements under eccentric compression. In the analysis, a finite element method was used based on an elasto-plastic constitutive law by Drucker-Prager with hardening and softening for concrete and an elasto-plastic constitutive law by von Mises for reinforcement. The effects of boundary conditions at the element ends, eccentricity of the compressive load, element slenderness, area of the longitudinal and horizontal reinforcement on the load bearing capacity of elements were studied. The effect of the mesh refinement on the bearing capacity of elements was also analysed. A satisfactory agreement with model tests was achieved.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2002, 6, 3; 411-428
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of extended finite element method to cracked concrete elements – numerical aspects
Autorzy:
Bobiński, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/230574.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
beton
pękanie
metoda elementów skończonych rozszerzona
implementacja
concrete
crack
extended finite element method
implementation
Opis:
The paper deals with the application of the eXtended Finite Element Method (XFEM) to simulations of discrete macro-cracks in plain concrete specimens under tension, bending and shear. Fundamental relationships and basic discrete constitutive laws were described. The most important aspects of the numerical implementation were discussed. Advantages and disadvantages of the method were outlined.
Źródło:
Archives of Civil Engineering; 2012, 58, 4; 409-431
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental investigations of strain localization in concrete using Digital Image Correlation (DIC) technique
Autorzy:
Kozicki, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/241130.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
concrete beams
digital image correlation
fracture process zone
strain localization
three-point bending
Opis:
The paper presents results of experimental investigations of strain localization in concrete using a non-destructive method called Digital Image Correlation (DIC) technique. This technique measures surface displacements from digital images. The model tests were carried out with notched concrete specimens under three-point bending. Three different beam sizes and two different concrete mixes were used. During experiments, load--deflection curves and evolution of fracture process zone were determined. The measured size effect in strength was compared with the deterministic size effect law by Bazant (1984) and experimental results by Le Bellégo et al (2003).
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2007, 54, 1; 3-24
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational modelling of concrete behaviour under static and dynamic conditions
Autorzy:
Marzec, I.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/202016.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
concrete
damage mechanics
dynamic loading
elasto-plasticity
non-local theory
viscosity
Opis:
The paper presents results of FE simulations of the concrete behaviour under quasi-static and dynamic loading. For quasi-static cyclic analyses, an enhanced coupled elasto-plastic-damage constitutive model has been used. To take the effect of the loading velocity into account, viscous and inertial terms have been also included. To ensure the mesh-independence and to properly reproduce strain localization in the entire range of strain rates, a constitutive formulation has been enhanced by a characteristic length of micro-structure by means of a non-local theory. Numerical results have been compared with some corresponding laboratory tests.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2013, 61, 1; 85-96
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stochastic FE-analysis of shear localization in 2D granular material within a micro-polar hypoplasticity
Autorzy:
Tejchman, J.
Górski, J.
Powiązania:
https://bibliotekanauki.pl/articles/241120.pdf
Data publikacji:
2006
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
granular materials
micro-polar hypoplasticity
shear localization
correlated random field
void ratio
Opis:
The paper deals with investigations of the effect of the stochastic distribution of the initial void ratio in granular bodies on shear localization during shearing of an infinite granular layer 500 mm high with free dilatancy under plane strain conditions. The initial void ratio was assumed to be stochastic with a correlated random field generated by a conditional rejection method by Walukiewicz et al (1997). To simulate mechanical behaviour of a cohesionless granular material during a monotonous deformation path, a micro-polar hypoplastic constitutive law was used, which takes into account particle rotations, curvatures, non-symmetric stresses, couple stresses and the mean grain diameter as a characteristic length. The proposed model captures the salient mechanical features of granular bodies in a wide range of densities and pressures with a single set of constants. In addition, the comparative FE-analyses were carried out with a uniform and spatially non-correlated random fields of the initial void ratio.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2006, 53, 4; 353-379
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulations of fracture in concrete elements using continuous and discontinuous models
Symulacje zarysowania w elementach betonowych z zastosowaniem podejścia ciągłego i nieciągłego
Autorzy:
Bobiński, J.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/368938.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
beton
nielokalność
plastyczność
kontynualna mechanika uszkodzeń
XFEM
concrete
non-locality
plasticity
damage mechanics
Opis:
The paper presents results of numerical simulations of fracture in concrete using two different approaches. First, fracture was modelled in a smeared way by an elasto-plastic and a damage continuum model. In elasto-plasticity, a Rankine criterion was used. The degradation of the stiffness in the damage model was described as a scalar variable of an equivalent strain measure. To ensure mesh-independent results, a non-local theory was used. Second, fracture was simulated as discontinuities with the aid of cohesive elements and Extended Finite Element Method (XFEM). The experimental benchmark test for concrete by Nooru-Mohamed under mixed mode conditions was modelled. The obtained numerical results were compared with the corresponding experimental ones.
W pracy przedstawiono wyniki symulacji numerycznych MES pękania w betonie z wykorzystaniem dwóch różnych podejść. Po pierwsze, zastosowano ciągły (przesmarowany) opis rys w teorii plastyczności oraz model degradacji modułu sprężystości z różnymi opisami odkształcenia zastępczego w ramach kontynualnej mechaniki uszkodzeń. Oba prawa rozszerzono o długość charakterystyczną mikrostruktury w ramach teorii nielokalnej w celu uzyskania wyników niezależnych od siatki MES. Po drugie, jako alternatywę do symulacji propagacji rys zastosowano nieciągły opis pola przemieszczeń, wykorzystując elementy kohezyjne oraz rozszerzoną metodę elementów skończonych XFEM. Przeprowadzono symulacje numeryczne testu Nooru-Mohamada z jednoczesnym rozciąganiem i ścinaniem betonu. Uzyskane wyniki numeryczne porównano z wynikami doświadczalnymi.
Źródło:
Mechanics and Control; 2011, 30, 4; 183-193
2083-6759
2300-7079
Pojawia się w:
Mechanics and Control
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania wytrzymałościowe nowych paneli kompozytowych w budownictwie mieszkaniowym
Strength testing of new composite panels in residential construction
Autorzy:
Smakosz, Ł.
Tejchman, J.
Powiązania:
https://bibliotekanauki.pl/articles/160617.pdf
Data publikacji:
2012
Wydawca:
Polski Związek Inżynierów i Techników Budownictwa
Tematy:
panel kompozytowy
panel konstrukcyjno-izolacyjny
właściwości mechaniczne
okładzina cementowo-magnezjowa
rdzeń styropianowy
composite panel
structural insulated panel
mechanical properties
magnesia cement lining
EPS core
Opis:
W artykule przedstawiono wyniki niektórych badań wytrzymałościowych nowych na polskim rynku budowlanym paneli kompozytowych, które mogą być stosowane jako elementy ścienne, stropowe i dachowe. Panele składają się z 2 sztywnych okładzin cementowo-magnezjowych zbrojonych włóknem szklanym połączonych klejem z miękkim rdzeniem ze styropianu. Panele charakteryzują się m.in. niskim ciężarem, szybkim i łatwym montażem, wysoką wytrzymałością, ognioodpornością i izolacyjnością cieplną.
This paper presents the results of strength tests carried out on composite panels, newly introduced to the Polish market, which might be used as elements of walls, ceilings and roofs. The panels consist of two rigid outer layers of magnesia cement reinforced with glass fibre, glued to a soft core of expanded polystyrene. The features offered by the panels include low weight, fast and easy assembly, high strength, fire resistance and thermal insulation properties.
Źródło:
Przegląd Budowlany; 2012, R. 83, nr 7-8, 7-8; 43-47
0033-2038
Pojawia się w:
Przegląd Budowlany
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 38

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