Wyniki wyszukiwania dla: STRUCTURAL ANALYSIS OF COLUMNS - MOST Wiedzy

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Wyniki wyszukiwania dla: STRUCTURAL ANALYSIS OF COLUMNS

Wyniki wyszukiwania dla: STRUCTURAL ANALYSIS OF COLUMNS

  • Jacek Chróścielewski prof. dr hab. inż.

  • The buckling analysis of a cold-formed steel C-sectional column resting on an elastic foundation

    The paper is focused on stability analysis of different models of steel cold-formed C-section column. The analysed element may be applied as a primary load-bearing member in steel trusses or silo columns. The column can be used as a support for a wall of roof plates made of corrugated sheets. The wall sheeting that restrains the column against buckling may be considered as an elastic foundation. Due to the design solutions the...

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  • Distortional buckling of composite thin-walled columns of a box-type cross section with diaphragms

    Publikacja

    Distortional buckling of axially compressed columns of box-like composite cross sections with andwithout internal diaphragms is investigated in the framework of one-dimensional theory. The channel membersare composed of unidirectional fibre-reinforced laminate. Two approaches to the member orthotropic materialare applied: homogenization based on the theory of mixture and periodicity cells, and homogenization basedon the Voigt–Reuss...

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  • Axial capacity of steel built-up battened columns

    Publikacja

    - Rok 2021

    This paper deals with the numerical investigation aimed to study the axial capacity of pin-ended steel built-up columns. Three methods of calculating forces in chords and batten, taking into account the material and geometric imperfections specified in the Eurocode 3 are considered. The aim of this study was to compare different methods allowing the calculation of the column load capacity and determine a simpler and faster method...

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  • Effect of initial imperfection on buckling of thin-walled I columns

    Publikacja

    Effects of initial geometrical imperfections on critical buckling loads of thin-walled I columns are investigated. Torsional and flexural buckling are taken into account. The column behaviour is described in accord to the theory of thin-walled beams with nondeformable cross-section. Some numerical examples and conclusions related to effects of imperfections on properties of the critical loads are presented.

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  • Corrosion mechanisms in columns for atmospheric distillation of crude oil

    Publikacja

    - Ochrona przed Korozją - Rok 2023

    The paper presents the most common corrosion processes occurring in the columns for atmospheric distillation of crude oil. It describes the mechanisms leading to formation of the chemical compounds, which contribute to corrosion phenomena. The main technological factors influencing corrosion processes have been indicated. The paper also presents the interactions between particular corrosion mechanisms resulting in acceleration...

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  • Enhancing the Seismic Resistance of Columns by GFRP Confinement Using Flexible Adhesive-Experimental Study

    Publikacja

    In this paper, the results of two experiments, focused on testing the effectiveness of a method of enhancing the seismic (dynamic) resistance of masonry columns with the use of flexible polymer adhesive, are shown. The first experiment was devoted to investigate the damping properties of a polymer working between two stiff layers, whereas the aim of the second one was to verify if the identified damping properties of the polymer...

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  • Installation of CMC columns in overconsolidated clays

    Publikacja

    - Rok 2017

    During rigid inclusions execution in the subsoil some monitoring data are registered by a drilling rig for quality control. The use of these data can improve the design procedure of soil improvement as they can provide some information about the position of bearing strata and the energy necessary to install the column in the ground. In this paper the parameters registered in a drilling machine are described, the installation...

  • Jarosław Chojnacki prof. dr hab. inż.

    Urodzony w 1961 w Bydgoszczy, absolwent Technikum Chemicznego im. I. Łukasiewicza w Bydgoszczy. Studia chemiczne ukończył na Wydziale Chemicznym Politechniki Gdańskiej w 1986 roku, broniąc pracy dotyczącej elektrod jonoselektywnych. Późniejsze badania związane były z syntezą organiczną i krzemoorganiczną a od 2002 roku z krystalografią. Praca doktorska dotyczyła silanotiolanów miedziowców, a dysertacja habilitacyjna (2010) opisywała...

  • Distortional buckling of thin-walled columns of closed quadratic cross-section

    The 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...

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  • Marcin Kujawa dr hab. inż.

    Marcin Kujawa ukończył studia na Wydziale Budownictwa Lądowego Politechniki Gdańskiej w 1999 roku, uzyskując stopień magistra inżyniera w specjalności mosty. Stopień naukowy doktora nauk technicznych w dziennie: budownictwo, pod kierunkiem profesora Czesława Szymczaka, uzyskał w 2007 roku na Wydziale Inżynierii Lądowej Politechniki Gdańskiej, broniąc pracę doktorską, pt.: Statyka i analiza wrażliwości rusztów zbudowanych z prętów...

  • Buckling of braced frames

    Publikacja

    - Rok 2009

    In this paper the classical Winter model, developed originally for columns is applied for frame structures and compared with the results of parametric study of frame with bracing. Sensitivity analysis of critical loads of frame due to bracing stiffness is carried out and the threshold bracing stiffness for full bracing is found. In the non-linear statical analysis the forces in bracings are calculated.

  • Concrete-filled FRP tubular members in marine and bridge structures

    Publikacja

    - Rok 2020

    Concrete core of the concrete-filled tubes (CFTs) with circular cross-section is in the case of an axial compression subjected to a spatial state of compressive stresses. This state leads to enhancement in the concrete strength. The enhancement is utilized in Eurocode 4 design procedures for CFSTs (i.e. CFTs with tube made of steel). The structural design of CFFTs (i.e. CFTs with tube made of Fibre Reinforced Polymer - FRP) is...

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  • Badania eksperymentalne słupów CFST z betonem zwykłym i ekspansywnym

    Praca przedstawia badania eksperymentalne ponad 40 słupów CFST. Analizie poddano wyniki siły niszczącej słupy w aspekcie grubości stalowego płaszcza, smukłości słupa, rodzaju betonu wypełniającego stalową rurę (zwykły i ekspansywny) i jego wytrzymałości a także sposobu obciążania słupa (przez rdzeń lub przez cały przekrój). Sprawdzono efektywność słupów CFST z użyciem betonu ekspansywnego i zwykłego rozumianą jako stosunek nośności...

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  • The use of GFRP tubes as load-bearing jackets in concrete-composite columns

    Publikacja

    The paper presents the fields of applications of polymer composites in building structures. The use of composite glass fibre tubes is discussed in more detail. The laboratory methods used to test the mechanical properties of these pipes are presented. An original research program is presented, including six concrete-filled glass fibre tubes. The cylinders and columns made in this way were tested for their axial load capacity. Conclusions...

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  • Analiza możliwości wykorzystania trójosiowego stanu naprężenia w betonie ściskanych słupów żelbetowych.

    W artykule przeprowadzono analizę możliwości wykorzystania trójosiowego stanu naprężeń ściskających w słupach uzwojonych i słupach CFST. Przeprowadzono także analizę możliwości zwiększenia efektywności uzwojenia i stalowego płaszcza przez zastosowanie betonu ekspansywnego. Przeprowadzone analizy opracowano na podstawie badań własnych autorów.

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  • Increasing the lifetime of engineering structures through the use of composite laggings

    Publikacja

    The use of composite laggings prevents concrete (chemical and biological) corrosion. Columns coated with composite or reinforced composite are more resistant to negative environmental impact on concrete or steel. The mechanical properties of the reinforced casing also cause that these types of columns are more resistant to lateral forces. The applied casing limits carbonization of concrete and cyclical freezing and thawing with...

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  • Torsional buckling and post-buckling of columns made of aluminium alloy

    The paper concerns torsional buckling and the initial post-buckling of axially compressed thin-walled aluminium alloy columns with bisymmetrical cross-section. It is assumed that the column material behaviour is described by the Ramberg–Osgood constitutive equation in non-linear elastic range. The stationary total energy principle is used to derive the governing non-linear differential equation. An approximate solution of the equation...

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  • Local buckling of compressed flange of cold-formed channel members made of aluminum alloy

    Publikacja

    The paper deals with local buckling of a compressed single flange of thin-walled channel cold- formed columns and beams made of aluminum alloy. Material is described by means of the Ramberg-Osgood constitutive equation. Axial compression of the columns and beams undergoing bending is taken into consid- eration. A simple model of the member flange in the form a long beam elastically connected to the web is used to find the critical...

  • Buckling of frame braced by linear elastic springs

    In the design codes and specifications, simplifed formulae or diagrams are given for determining the buckling lengths of frame columns based on the ruling criterion of considering frames as sway or non sway. Due to the fact that, the code formulae utilize onlylocal stifness distributions, these formulae may yield in certain cases rather erroneous results. In most code formulas a case of weakly braced frames is usually not considered.In...

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  • Marta Kuc-Czarnecka dr

    Marta Kuc-Czarnecka jest zastępczynią kierownika Katedry Statystyki i Ekonomii na Wydziale Zarządzania i Ekonomii Politechniki Gdańskiej. Pełni również funkcję pełnomocniczki Dziekana ds. akredytacji AMBA. Jest współzałożycielką Rethinking Economics Gdańsk oraz członkinią Fundacji im. Edwarda Lipińskiego na rzecz promocji pluralizmu w naukach ekonomicznych. W latach 2018-2022 była ekspertką Europejskiej Fundacji na Rzecz Poprawy...

  • Komputerowa Analiza Konstrukcji 2022/2023

    Kursy Online
    • Ł. Żmuda-Trzebiatowski
    • M. Krajewski
    • M. Sondej
    • M. A. Zmuda Trzebiatowski
    • K. Żerdzicki
    • Ł. Smakosz
    • P. Kłosowski

    Budownictwo, rok 3, sem 6 Celem kursu jest zapoznanie się z podstawami metod komputerowej analizy konstrukcji od strony teoretycznej oraz praktycznej, poprzez pracę w środowisku obliczeniowym metody elementów skończonych na przykładzie programu Autodesk Robot Structural Analysis Professional.

  • Komputerowa Analiza Konstrukcji 2023/2024

    Kursy Online
    • Ł. Żmuda-Trzebiatowski
    • A. Ambroziak
    • M. Krajewski
    • M. Sondej
    • M. A. Zmuda Trzebiatowski
    • K. Żerdzicki
    • Ł. Smakosz
    • P. Kłosowski

    Budownictwo, rok 3, sem 6 Celem kursu jest zapoznanie się z podstawami metod komputerowej analizy konstrukcji od strony teoretycznej oraz praktycznej, poprzez pracę w środowisku obliczeniowym metody elementów skończonych na przykładzie programu Autodesk Robot Structural Analysis Professional.

  • Selected concentration techniques for gas chromatographic analysis of environmental samples

    Publikacja

    The paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...

  • Miniaturized Solid Phase Extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 1

    Publikacja

    - TRAC-TRENDS IN ANALYTICAL CHEMISTRY - Rok 2023

    Solid Phase Extraction (SPE) has been practiced in a modern form for more than half a century. It was constantly developing, driven by the analysts needs. These needs are coming from the importance to select an appropriate analytical method, which should have satisfactory accuracy, precision and sensitivity. In the case of sorbent-based microextraction techniques, the choice of miniaturized variants that meet these requirements...

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  • Load introduction to composite columns revisited—Significance of force allocation and shear connection stiffness

    Publikacja

    - ENGINEERING STRUCTURES - Rok 2023

    The AISC 360-16 Specification recommends that the design shear force between parts of a composite column in the load introduction area shall be calculated based on the force allocation at ultimate limit state. Applicability of this straightforward method to the load levels that usually arise in slender composite columns is questionable, as this capacity-based force allocation is only true when the axial force is equal to the plastic...

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  • 9-(Trichloroacetylimino)acridine monohydrate

    Publikacja
    • J. Meszko
    • K. Krzymiński
    • A. Konitz
    • J. Błażejowski

    - ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS - Rok 2002

    The title compound, alternatively called N-acridin-9(10H)-yl­idene-2,2,2-tri­chloro­acet­amide mono­hydrate, C15H9Cl3N2O·H2O, crystallizes in space group P21/c with Z = 4. The acridine moieties are arranged in layers, tilted at an angle of 15.20 (4)° relative to the ac plane, while adjacent mol­ecules pack in a head-to-tail manner. Acridine and water mol­ecules form columns along the b axis held in place by a network of hydrogen...

  • Monitoring system of the road embankment

    The paper presents the monitoring system of the embankment supported on concrete columns and overlaid by a load transfer platform (LTP) with the embedded steel grid. This field investigation was to study the complex inter-action between the columns, the LTP layer, and steel reinforcement via full-scale in situ measurements during erection of the embankment. The study was focused on the behaviour of steel reinforcement and the behaviour...

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  • Shaking table experimental study on damage mechanism of the disconnecting switch under seismic excitation

    The efficiency of the energetic network is a very import safety issue in the region experienced by the earthquake. High voltage disconnecting switches are important elements of the energetic infrastructure used to separate electric circuits (i.e. during repairs), which should not be damaged remaining fully operational. The aim of the paper is to show the results of the shaking table experimental investigation focused on damage...

  • Buckling of simplified models of silo with corrugated walls and vertical stiffeners

    Publikacja

    The paper deals with buckling of cylindrical silos composed of corrugated sheets and vertical stiffeners (columns). Comprehensive finite element analyses were carried out for a perfect silo by means of a linear buckling approach. Corrugated walls were simulated as an equivalent orthotropic shell and vertical thin-walled columns as beam elements. Calculations for perfect silos with different numbers of columns made it possible to...

  • Influence of stirrups in a concrete shell on strengthening reinforced concrete column

    Publikacja

    - Rok 2014

    Twelve concrete columns, with a 150x150mm square section and three columns with a circular section (d=200mm), are tested to investigate the effect of strengthening by RC jacket. Based on a confined concrete model for axial static loading, an analytical methods, reported in the literature are proposed to predict the behavior of columns with RC jacket. The results support the conception that the effect of strengthening depends...

  • Numerical Analysis of a Steel Frame Building with Soft-storey Failure under Ground Motion Excitation

    The aim of this paper is to show the results of a numerical analysis focused on the behaviour of multi-storey steel frame building that suffers from a soft-storey failure under ground motion excitation. A numerical model of the structure was created in FEM computer software and was exposed to an impact that would have been generated after a soft-storey failure due to falling of the upper floors. During the analysis, the whole structure...

  • Buckling Analysis of Cold Formed Silo Column

    The paper is devoted to stability analysis of different models of steel cold formed silo column. The steel cylindrical silos are often composed of corrugated walls and vertical open-sectional columns uniformly placed along the silo circumference. Both the whole 3D silo, a simplified model consisting of one column with a part of the silo walls, and a single column resting on elastic foundation provided by the silo walls were analyzed....

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  • Ahmed Manguri PhD Student

    Osoby

    Jestem doktorantem I roku na Politechnice Gdańskiej w zakresie Dynamicznej Analizy Konstrukcji pod kierunkiem prof. Jankowskiego. Ukończyłem studia magisterskie z inżynierii strukturalnej na Uniwersytecie Cardiff w Wielkiej Brytanii oraz licencjat z inżynierii lądowej na Uniwersytecie Koya w Kurdystanie. Od 2016 roku jestem pracownikiem naukowym Uniwersytetu Raparin w Kurdytanie.

  • Mechanics of materials (PG_00057378), W/Ć, BM, II stop., sem1,3, lato, 2023/24

    Kursy Online
    • B. Rozmarynowski
    • P. M. Bielski

    The aim of this course is providing knowledge in the field of analysis and solving problems of mechanics and strength of one-dimensional systems (bars, beams, frames) and selected two-dimensional systems (shields, plates); preparing the student to solve problems involving complex cases of material strength; developing the ability to assess the stability of structural elements (forms of stability loss, critical forces); consolidation...

  • Pore Water Pressure Development in Soft Soil due to Installation and Loading of Controlled Modulus Columns

    Excess pore water pressure (EPWP) development and decay due to the installation and static loading tests of controlled modulus columns (CMC) in soft soil was measured with piezometers equipped with low air entry (LAE) filters and a piezocone (CPTU) equipped with a high air entry (HAE) filter. The HAE filter allows for detailed detection of EPWP in short time intervals during construction of CMC. The influence zone due to the installation...

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  • Determination of the shape of the CFGFT cylindrical column based on laboratory tests

    Analyses were carried out on glass-fibre-reinforced polymer tube columns with reference to laboratory tests. The angles of the glass fibre beams were 20◦, 55◦ and 85◦. The study employed non-classical operational calculus. Various modulated harmonic signal shapes were considered for columns and tubes at buckling. The buckling loads were assessed and compared for different models.

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  • Long-term operating conditions for different sorption materials to capture phosphate from domestic wastewater

    Publikacja

    - Sustainable Materials and Technologies - Rok 2022

    This paper presents the results of a study on the possibility of applying various configured filters filled with a mixture of Rockfos® and Leca® material for the effective capture of phosphate from domestic wastewater. The tests were carried out for two years at two wastewater flow rates (20 and 40 L/day) in three pairs of filtration columns with a volume of filter material equal to 20 liters each. Columns 1A and 1B were filled...

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  • COMPUTER-AIDED CONSTRUCTION AT DESIGNING REINFORCED CONCRETE COLUMNS AS PER EC

    The article presents the author’s computer program for designing and dimensioning columns in reinforced concrete structures taking into account phenomena affecting their behaviour and information referring to design as per EC. The computer program was developed with the use of C++ programming language. The program guides the user through particular dimensioning stages: from introducing basic data such as dimensions, concrete...

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  • Analiza obudowy wykopu dla budynku z kondygnacją podziemną

    Publikacja

    W pracy poruszono tematykę analizy obudowy wykopu dla budynku z jedną kondygnacją podziemną, zlokalizowanego w gęstej zabudowie śródmiejskiej. Obliczenia przeprowadzono za pomocą dwóch programów obliczeniowych: GEO5 (moduł: Ściana analiza) i Autodesk Robot Structural Analysis Professional. Całość wyników podsumowano, a wnioski sformułowano w odniesieniu do obecnej sytuacji na rynku budowlanym, charakteryzującej się coraz to trudniejszymi...

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  • Krzysztof Jan Kaliński prof. dr hab. inż.

    Ukończył studia magisterskie na Wydziale Mechanicznym Technologicznym (MT) PG (1980, dyplom z wyróżnieniem). Stopień doktora otrzymał na Wydziale Budowy Maszyn PG (1988, praca wyróżniona), stopień doktora habilitowanego na Wydziale Mechanicznym (WM) PG (2002, praca wyróżniona), a tytuł profesora nauk technicznych – w 2013 r. Od 2015 r. jest profesorem zwyczajnym, a od 2019 r. - profesorem. Obszar jego badań naukowych obejmuje:...

  • Ocena wzmocnienia podłoża metodą wymiany dynamicznej na podstawie próbnych obciążeń kolumn

    Analiza wykonanego wzmocnienia słabego podłoża gruntowego pod nasyp drogowy w technologii kolumn DR na przykładzie obwodnicy Brodnicy. Omówienie warunków geotechnicznych podłoża i zastosowanych rozwiązań. Analiza wsteczna na podstawie wyników próbnych obciążeń kolumn oraz pomiarów osiadań wzmocnionego podłoża całego obszaru. Porównanie uzyskanych wyników i wnioski.

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  • Transportable, Portable and Micro Gas Chromatographs

    Significant benefits can be obtained by miniaturization of conventional benchtop gas chromatographs. The attractive features arising from miniaturization include low-power requirements, low heat capacity of separation columns, low consumption of mobile phase, enhanced performance, higher portability, and easily coupling to detectors and secondary chromatographic systems. In separation sciences, including gas phase separations,...

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  • Application of the ‘CPT 2012’model of AFNOR standard for column design in Poland–Jazowa case study

    Publikacja

    his paper presents the ‘CPT 2012’ model incorporated into the AFNOR NF P94-262:2012-07, French standard for pile design fully compatible with Eurocode 7, to the wider Polish audience. The bearing capacity of three reference columns for Vistula Marshlands have been calculated according to ‘CPT 2012’ model and AFNOR recommendations. Then, the design resistances have been compared with ultimate column bearing capacity measured during...

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  • Polycyclic aromatic hydrocarbons as test probes to investigate the retention behavior of 1,3-alternate calix[4]arene silica-bonded stationary phases

    Publikacja

    A series of polycyclic aromatic hydrocarbons (PAHs) of different size and shape has been used to characterize the chromatographic behavior of five calix[4]arene stationary phases in 1,3-alternate conformation synthesized in our laboratory. The selection of linear, fourring nonlinear, and five-ring PAHs gave data on selectivity changes across range of the calix[4]arene columns. Retention of the 12 aromatic solutes has been evaluated...

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  • Comparison of bacterial production in the water column between two Arctic fjords, Hornsund and Kongsfjorden (West Spitsbergen)

    Publikacja

    - OCEANOLOGIA - Rok 2017

    Bacterial production and the accompanying environmental factors were measured in the water columns of two Arctic fjords during the cruise in July and August 2013. Water samples were collected at six stations located in the central part of Hornsund and Kongsfjorden. In Hornsund, where average water temperatures were 1.25-fold lower than in Kongsfjorden, the bacterial production was twice as high (0.116 ± 0.102 vs 0.05 ± 0.03 mg...

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  • Experimental study on earthquake-induced pounding between steel structures

    Publikacja

    Pounding between adjacent structures has been repeatedly observed during major earthquakes. The phenomenon may cause some local damage at the points of interactions, it may also lead to substantial destruction, permanent deformations or total collapse of colliding structures. The effects of earthquake-induced structural pounding have been studied for more than three decades now. However, most of the studies concerned masonry as...

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  • Application of electronic nose based on fast GC for comparison of aroma profiles of homemade cherry "Nalewka" made with addition of different amount of sugar

    Nalewka is a traditional Polish homemade spirit beverage and there are many different recepies for the production of nalewkas. However, it is not knownwhat amount of sugar can have influence of their aroma profiles. There is little information on the comparison of aroma profiles of Polish cherry nalewkas made with addition of different amount of sugar. For this purpose electronic nose based on fast GC has been used. Electronic...

  • Application of electronic nose based on fast GC for comparison of aroma profiles of homemade cherry "Nalewka" made with addition of different amount of sugar

    Nalewka is a traditional Polish homemade spirit beverage and there are many different recepies for the production of nalewkas. However, it is not knownwhat amount of sugar can have influence of their aroma profiles. There is little information on the comparison of aroma profiles of Polish cherry nalewkas made with addition of different amount of sugar. For this purpose electronic nose based on fast GC has been used. Electronic...

  • Method of determining the residual fluxes in transformer core

    Publikacja

    - Rok 2017

    The article presents the method of calculating the residual induction in transformer columns. The method is based on measurement of the magnetic induction in selected points around the transformer core. The values of residual induction are calculated as linear combination of the results of measurement.

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