Search
Search results for: THIN STRUCTURES
-
THIN-WALLED STRUCTURES
Journals -
Application of superelements in static analysis of thin‐walled structures
Publication -
Application of superelements in static analysis of thin-walled structures.
PublicationW pracy omówiono koncepcję zastosowania superelementów MES w statycznej analizie konstrukcji cienkościennych ze szczególnym uwzględnieniem belek cienkościennych wzmocnionych stężeniami oraz węzłów ram zbudowanych z elementów cienkościennych. W zamieszczonych przykladach numerycznych rozwiazania uzyskane z pomoca superelementów porównano z wynikami otrzymanymi przy gestej dyskretyzacji MES całej konstrukcji elementami powłokowymi.
-
Experimental study and numerical calculations in the analysis of thin-walled structures
Publication -
Modelling and static analysis of thin-walled structures, problems and applications
PublicationW pracy przedstawiono pewne problemy związane z modelowaniem i analizą statyczną konstrukcji cienkościennych: belek, ram i rusztów zbudowanych z elementów o bisymetrycznym przekroju poprzecznym. Zachowanie elementów opisano za pomocą klasycznej teorii prętów cienkościennych o przekroju nieodkształcalnym. Uwzględniono tym samym efekty bimomentowe od skręcania belek. Niestyty brakuje koniecznych do przeprowadzenia analizy styacznej...
-
Technologies for Joining and Forming Thin-Walled Structures in the Construction of Transportation Vehicles
PublicationEditorial
-
Spectroscopic studies of sol-gel derived thin film structures for integrated optics
PublicationPrzedstawiono wyniki badania struktur cienkowarstwowych wykonywanych dla zastosowań w optyce zintegrowanej z polimerów hybrydowych (np. w postaci ścieżek śwaitłowodów planarnych). Jakość i jednorodność stuktur badano za pomocą mikroskopii ramanowskiej, mikroskopii optycznej i profilometrii światła białego. Wykonano porównanie wyników uzyskanych tymi trzema metodami.
-
A review of stability problems of thin-walled structures developed at Gdańsk University of Technology
PublicationW pracy podano przegląd problemów stateczności konstrukcji cienkościennych, które były przedmiotem badań na Politechnice Gdańskiej. Przedstawiono bibliografię obejmującą 75 prace podzielone na trzy grupy tematyczne: stateczność prętów i łuków, pokrytyczne zachowanie się elemntów oraz optymalne projektowanie i analizę wrażliwości.
-
Quality increase for single-welded joints of thin-walled structures by means of simulation modelling
PublicationThe Simulation calculation module and the SolidWorks software package have helped to define the optimal shape and dimensions of single-welded joints which may serve the basis for calculating the process parameters of welding. Having compared the models with different weld cross-sections the authors have defined that the weld height and width do not significantly affect the stress concentration, and the stress concentration and...
-
Electric-field-induced quenching of photoluminescence in photoconductive organic thin film structures based on Eu3+ complexes
PublicationW pracy badano elektrycznopolowe wygaszenie fotoluminescencji w organicznych kompleksach europu Eu(III) rozdyspergowanych w matrycy poliwęglan: dwuamina TPD. W układzie z elektrodami Al/Al obserwowano wygaszenie fotoluminescencji wywołane dysocjacją ekscytonów. W układzie z elektrodami ITO(+)/Au(-) oprócz dysocjacji ekscytonów obserwowano również silne wygaszenie ekscytonów na ładunku elektrycznym wstrzykniętym do próbki. Analiza...
-
The role of solvent solubility parameters in the formation of intermittent low and high molecular weight polystyrene rich structures in a thin film resulting from water vapor induced phase separation
Publication -
Junctions In Shell Structures: A Review
PublicationMany shell structures used in modern technology consist of regular shell parts joined together along their common boundaries. We review different theoretical, numerical, and experimental approaches to modelling, analyses and design of the compound shell structures with junctions. Several alternative forms of boundary, continuity and jump conditions at the singular midsurface curves modelling the shell junction are reviewed. We...
-
Sensitivity analysis of thin-walled members, problems and applications
PublicationPodano przegląd problemów analizy wrażliwości konstrukcji cienkościennych. Przedstawiono metody określania pierwszej wariacji zmiennych stanu takich jak: przemieszczenia, siły wewnętrzne, reakcje, częstości i postaci drgań własnych oraz obciążeń krytycznych ze względu na zmiany parametrów konstrukcji. Rozważania ograniczono do prętów cienkościennych o otwartym bisymetrycznym przekroju poprzecznym w ramach założeń teorii prętów...
-
Distortional buckling of thin-walled columns of closed quadratic cross-section
PublicationThe elastic stability of axially compressed column related to the cross-section distortion is investigated. Two kinds of closed quadratic cross-sections are taken into consideration with internal walls and without it. The governing differential equation is derived with aid of the principle of stationary total potential energy. The critical loads for the simply supported columns are found in an analytical form and compared with...
-
Numerical investigation into plastic hinge formation in arched corrugated thin-walled profiles
Publication -
Dynamic FE simulations of buckling process in thin-walled cylindrical metal silos
PublicationW artykule przedstawiono wyniki dynamicznej analizy wyboczeniowej cienkościennych silosów metalowych o przekroju kołowym. Analizy MES wykonano dla wstępnych imperfekcji geometrycznych o różnym kształcie i amplitudzie. Wyniki analizy dynamicznej porównano z analizami statycznymi.
-
Numerical analysis of influence of intermediate stiffeners setting on the stability behaviour of thin-walled steel tank shell
Publication -
Determination of buckling strength of silos composed of corrugated walls and thin-walled-columns using simplified wall segment models
PublicationW artykule przedstawiono wyniki obszernych analiz numerycznych wyboczenia i stateczności metalowych silosów z blachy falistej wzmocnionych cienkościennymi słupami. Wykonano analizy liniowe i nieliniowe. Do obliczeń zaproponowano proste modele segmentów ścian zamiast skomplikowanych modeli całych silosów. Otrzymano bardzo dobrą zgodność wyników numerycznych. Wyniki obliczeń numerycznych porównano dodatkowo z wynikami normowymi.
-
Deformation of thin metal and composite sheets by using anti-buckling fixture for large deformation under tension–compression cyclic loading
Publication -
Large thermo-elastic displacement and stability FEM analysis of multilayered plates and shells
PublicationThe paper concerns the load capacity analysis of thermally loaded multilayered plates and shells. The multilayered body is treated as an equivalent single layer whose kinematics is consistent with first order shear deformation theory. The authors focus on the thermo-elastic stability problem of the thin-walled structures. The equilibrium paths are traced with the use of Riks-Wempner-Ramm algorithm. By making use of the Tsai-Wu...
-
On local buckling of cold-formed channel members
PublicationThe paper deals with local buckling of the compressed flanges of cold-formed thin-walled channel beams subjected to pure bending or axially compressed columns. Arbitrarily shaped flanges of open cross-sections and the web-flange interactions are taken into account. Buckling deformation of a beam flange is described by displacement related to torsion of the flange about the line of its connection with the web. Total potential energy...
-
Buckling and initial post-local buckling behaviour of cold-formed channel member flange
PublicationThe initial post-buckling behaviour of a cold-formed channel member flange after its local buckling is investigated. An axially compressed column or beam subjected to pure bending is considered. The member material is assumed to follow a linear stress-strain relationship. The governing non-linear differential equation of the problem is derived using the minimum total potential energy principle. An approximate solution for the equation...
-
Nonlinear FEM 2D failure onset prediction of composite shells based on 6-parameter shell theory
PublicationWithin the framework of the nonlinear 6-parameter shell theory with the drilling rotation and asymmetric stress measures, the modifications of Tsai-Wu and Hashin laminate failure initiation criteria are proposed. These improvements enable to perform first ply failure estimations taking into account the non-symmetric stress measures. In order to check the validity of the proposed criteria, finite element analyses are performed with...
-
Experimental method to evaluate the load-carrying capacity of double corrugated sheet profiles
Publication -
Experimental and numerical studies of double corrugated steel arch panels
Publication -
Numerical and experimental investigation of rotational stiffness of zed-purlins connection with sandwich panels
PublicationA rotational resistant stiffness of the zed-purlins connection with sandwich panels is investigated. A simple finite element method model of the connection is proposed. The numerical analysis of the model performed by ABAQUS software, in physically linear and geometrically nonlinear ranges, leads to the rotational resistant stiffness sought. The numerical solution obtained is verified experimentally. Two variants of distribution...
-
Stability and initial post-buckling behaviour of frame system with vertical bracings
PublicationStalowe hale są budowane jako układ ram płaskich połączonych stężeniami dachowymi i stężeniami pionowymi w postaci krzyżujących się prętów. W pracy przedstawiono analizę stateczności i zachowania pokrytycznego takiego układu poddanego działaniu obciążeń pionowych. Korzystając z warunków stacjonarności całkowitej energii potencjalnej wykazano, że punkt bifurkacji utraty stateczności jest niesymetryczny i niestateczny. Oznacza to,...
-
Stability of trusses with linear elastic side-supports
PublicationThe present research is devoted to study of a lateral buckling of truss with linear elastic side supports. The elastic support reaction in relation to force in compressed chord and coefficient of buckling length related to side support distance are also calculated. The effect of slope of side support on limit force is also considered. The nonlinear analysis of two roof trusses are carried out. The results are compared to design...
-
Advanced numerical modelling for predicting residual compressive strength of corroded stiffened plates
PublicationAn advanced methodology for predicting the residual compressive strength of corroded stiffened plates is developed here using the non-linear finite element method. The non-uniform loss of a plate thickness is accounted for on a macro-scale. In contrast, mechanical properties are changed using the constitutive model to reflect the corrosion degradation impact on a micro-scale. Three different stiffened plate thicknesses are considered,...
-
Experimental investigation of joint with positive eccentricity in CFS truss
PublicationDue to technological restrictions, in the case of trusses made of CFS open cross-sections, positive eccentricities in the truss joints have become very frequent. Therefore studies concerning the load-bearing capacity of truss joints with positive eccentricity were undertaken. It was assumed that the resistance of cold-formed steel (CFS) open cross-section truss joints located on compression chords and with positive eccentricity...
-
Investigations of local/global buckling of cylindrical metal silos with corrugated sheets and open-sectional column profiles
PublicationArtykuł zajmuje się problemem lokalnego/globalnego wyboczenia w cylindrycznych metalowych silosach z blachy falistej z otwartymi cienkościennymi profilami słupowymi. Obliczenia wykonano w ramach liniowej teorii bifurkacji stosując metodę elementów skończonych w programie ABAQUS. Zbadano obszernie wpływ różnych parametrów (średnica i wysokość silosów, grubość blachy falistej, wielkość fali blachy, rozstaw słupów, przekrój słupów)...
-
Simulation of buckling process of cylindrical metal silos with flat sheets containing bulk solids.
PublicationW artykule symulowano proces wyboczenia w cylindrycznych metalowych silosach z płaskich blach wypełnionych materiałem sypkim. Wykonano analizy nieliniowe stosując MES dla silosów pustych i napełnionych. Zbadano wpływ wstępnych imperfekcji geometrycznych na nośność wyboczeniowo. Wyniki porównano z wynikami doświadczalnymi w Uniwersytecie Karlsruhe.
-
Critical assessment of Eurocode approach to stability of metal cylindrical silos with corrugated walls and vertical stiffeners.
PublicationPrzedmiotem artykułu było krytyczne oszacowanie podejścia w Eurokodzie odnośnie stateczności metalowych cylindrycznych silosów z blachy falistej i słupów. Obliczenia 3D wykonane stosując MES. Symulowano blachę gładką ze słupami belkowymi o zastępczej sztywności. W obliczeniach uwzględniono falistość blachy. Pokazano, że wzory normowe znacznie odbiegają od wyników MES.
-
3D buckling analysis of a cylindrical metal bin composed of corrugated sheets strengthened by vertical stiffeners
PublicationW artykule pokazano obszerne wyniki analizy wyboczeniowej 3D przy zastosowaniu metody elementów skończonych dla silosu złożonego z blachy falistej i słupów rozmieszczonych równomiernie wokół obwodu. Obliczenia wykonano dla silosu bez i z imperfekcjami geometrycznymi i obciążeniowymi. Wyniki obliczeń porównano z Eurokodem.
-
Buckling resistance of a metal column in a corrugated sheet silo - experiments and non-linear stability calculations
PublicationThe results of experimental and numerical tests of a single corrugated sheet silo column’s buckling resistance are presented in this study. The experiments were performed in a real silo with and without bulk solid (wheat). A very positive impact of the bulk solid on the column buckling resistance occurred. The experimental results were first compared to the buckling resistance calculated by Eurocode 3 formulae. The comparison revealed that...
-
Marcin Kujawa dr hab. inż.
PeopleI have graduated from the Faculty of Civil Engineering, Gdańsk University of Technology (https://pg.edu.pl/en) in 1999. I received my M.Sc. degree in civil engineering structures with specialization in bridge structures. Next, in 2007, I received my doctoral degree in technical sciences under the supervision of professor Czesław Szymczak (Scopus Author ID: 6603993146) at the Faculty of Civil Engineering, Gdańsk University of Technology....
-
Selected Stability Problems of Thin-Walled Columns and Beams
PublicationThe article reviews a number of papers in the light of buckling analy- sis of thin-walled columns and beams. Stability of thin-walled columns and beams are considered a vital engineering science issue in both historical and present-day approaches. The paper refers to the recent authors’ works of the 2012–2019 period, published in leading journals. Similar review of stability problems of thin-walled structures developed at Gdansk...
-
Thin-walled frames and grids - statics and dynamics
PublicationFrames and grids assembled with thin-walled beams of open cross-section are widely applied in various civil engineering and vehicle or machine structures. Static and dynamic analysis of theses structures may be carried out by means of different models, startingfrom the classical models made of beam elements undergoing the Kirchhoff assumptions to the FE discretization of whole frame into plane elements. The former model is very...
-
The Idea of Using Adhesive Bonds in Shaping of Cold-formed Thin-walled Beam-columns
PublicationThe chapter concerns the idea of using adhesive bonds in the shaping of cold-formed thin-walled beam-columns. The idea of adhesive-bonded connections is not new but is unlikely to have been used in the design and shaping of thin-walled beam-columns in civil engineering up to date. Metal bar structures, including (due to economic reasons) thin-walled structures, are the most common and effective means to build engineering superstructures/loadbearing...
-
Transformation of bimetallic Ag–Cu thin films into plasmonically active composite nanostructures
PublicationFormation of plasmonically active silver, copper and composite silver-copper nanostructures were studied in this paper. Metallic nanostructures were fabricated by thermal disintegration, so called dewetting, of the thin films in an argon atmosphere. The formation process of the nanostructures was in-situ observed by a novel method, based on resistance measurements. The influence of the material and thickness of the initial thin...
-
Minimal surfaces and conservation laws for bidimensional structures
PublicationWe discuss conservation laws for thin structures which could be modeled as a material minimal surface, i.e., a surface with zero mean curvatures. The models of an elastic membrane and micropolar (six-parameter) shell undergoing finite deformations are considered. We show that for a minimal surface, it is possible to formulate a conservation law similar to three-dimensional non-linear elasticity. It brings us a path-independent...
-
Investigation of natural frequencies of axially loaded thin-walled columns
PublicationThe paper deals with correlation between natural frequencies of two steel thin-walled columns and the corresponding applied load. The structures are made of cold-formed lipped channel sections. The columns lengths were assumed to follow two buckling patterns – global flexural and flexural-torsional buckling. In the thicker structure two material models were considered – linearly-elastic and elastic-perfectly plastic. Numerical...
-
Thermal Instability of Gold Thin Films
PublicationThe disintegration of a continuous metallic thin film leads to the formation of isolated islands, which can be used for the preparation of plasmonic structures. The transformation mechanism is driven by a thermally accelerated diffusion that leads to the minimalization of surface free energy in the system. In this paper, we report the results of our study on the disintegration of gold thin film and the formation of nanoislands...
-
On Von Karman Equations and the Buckling of a Thin Circular Elastic Plate
PublicationWe shall be concerned with the buckling of a thin circular elastic plate simply supported along a boundary, subjected to a radial compressive load uniformly distributed along its boundary. One of the main engineering concerns is to reduce deformations of plate structures. It is well known that von Karman equations provide an established model that describes nonlinear deformations of elastic plates. Our approach to study plate deformations...
-
Properties of Thermally Dewetted Thin Au Films on ITO-Coated Glass for Biosensing Applications
PublicationNoble metal nanostructures are object of great interest due to their unique optical and electronic properties exploited in nanotechnology, medicine, biochemistry, and surface-enhanced spectroscopies. In this work, the Au nanoparticle (NP) structures for application in biosensing obtained by dewetting are investigated in dependence on their preparation conditions. Structures are produced from thin Au films (5–30 nm) sputtered onto...
-
Au nanostructures coated with a ultrathin film of Al2O3 - measurements and FDTD simulations
Open Research DataGold plasmonic platforms have been coated with an ultra-thin films of aluminium oxide. Optical measurements, showing the influence of the thickness of Al2O3 on plasmon resonance position. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of...
-
Calculation of Resonance in Planar and Cylindrical Microstrip Structures Using a Hybrid Technique
PublicationA hybrid technique was employed for the analysis of the resonance frequency of thin planar and cylindrical microstrip structures with the patches of arbitrary geometry. The proposed technique utilizes a combination of Galerkin’s moment method and a finite-element method (FEM). In this approach, an FEM is adopted to calculate the patch surface current densities, and a method of moments is utilized to calculate the resonance frequencies...
-
UV-Vis measurements and SEM images of Ag nanostructures
Open Research DataUv-vis and SEM of Ag nanostructures. Structures were obtained by dewetting thin films. Various fabrication conditions i.e. temperature, time of the annealing and thickness of the initial layer were subsequently changed.
-
Study of the Layer-Type BST Thin Film with X-ray Diffraction and X-ray Photoelectron Spectroscopy
PublicationIn the present paper, results of X-ray photoelectron studies of electroceramic thin films of barium strontium titanate, Ba1xSrxTiO3 (BST), composition deposited on stainless-steel substrates are presented. The thin films were prepared by the sol-gel method. A spin-coating deposition of BST layers with different chemical compositions was utilized so the layer-type structure of (0-2) connectivity was formed. After the deposition,...
-
Raw data of AuAg nanoalloy plasmon resonances used for machine learning method
Open Research DataRaw data used for machine learning process. UV-vis measurements of AuAg alloyed nanostructures created from thin films. Plasmonic band position dependence on fabrication parameters. Small presentation reviewing achieved structures and their properties.