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1

Influence of Bimoment Restraints on the Load-Bearing Capacity of a Steel I-Beam

Wierzbicki Krzysztof

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 4

33--47

EN

The study presents an analysis of steel I-beam warping. The calculations were made for hot-rolled IPE200 hinged beams with different lengths. After determining load-bearing capacity using the GMNIA method, the beams were strengthened with bimoment restraints at each end. The changes in critical moment and load-bearing capacity were then evaluated. The study presents the manner in which the material and geometric imperfections have been determined. The GMNIA calculations were conducted using the Finite Element Method in Abaqus software. The results were then compared to results obtained with traditional methods and acquired from LT Beam software.

2

Numerical simulation of forming titanium thin-wall panels with stiffeners

Adamus Janina, Winowiecka Julita, Dyner Marcin, Lacki Piotr

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 1

54--62

EN

Due to the increase in the application of titanium components made of thin titanium sheets, in the work titanium panels made of 4 mm thick sheets are analysed. To increase the rigidity of the panels, some cross-shaped stiffeners were made. Such panels enable a reduction in weight while maintaining the existing strength of the drawn parts. Three kinds of commercially pure titanium are considered: Grade 1, 2 and 3. Numerical calculations were performed with PamStamp 2G based on the finite element method. The basic mechanical and technological properties of the analysed sheets, which are necessary for numerical modelling, were determined by static tensile testing. The friction coefficient was assumed based on the literature. On the basis of the performed numerical analyses, it was stated that the proper forming of panels with stiffeners depends not only on the drawability of the sheets but also on the technological parameters such as blank holder force and frictional conditions.

3

On stability of thin periodically, densely stiffened cylindrical shells

Tomczyk B.

Journal of Theoretical and Applied Mechanics

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2005

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Vol. 43 nr 2

427--455

EN

The aim of this contribution is to propose a new averaged nonasymptotic model of stationary stability problems for thin linear-elastic cylindrical shells reinforced by stiffeners which are periodically, densely spaced along one direction tangent to the shell midsurface. As a tool of modelling we shall apply the tolerance averaging technique. The resulting equations have constant coefficients in the periodicity direction. Moreover, in contrast with models obtained by the asymptotic homogenization technique, the proposed one makes it possible to describe the effect of the periodicity cell size on the global shell stability (a length-scale effect). It will be shown that this effect plays an important role in the shell stability analysis and cannot be neglected.

PL

W pracy zaproponowano nowy uśredniony nieasymptotyczny model służący do analizy stateczności cienkich liniowo-sprężystych powłok walcowych, periodycznie, gęsto użebrowanych w jednym kierunku stycznym do powierzchni środkowej. Przy wyprowadzaniu równań modelu wykorzystano znaną metodę tolerancyjnego uśredniania, zaproponowaną przez Woźniaka i Wierzbickiego (2000). Zastosowanie tej metody do znanych równań teorii powłok Kirchhoffa-Love'a doprowadziło do modelu reprezentowanego przez równania różniczkowe cząstkowe o stałych współczynnikach w kierunku periodyczności, zależnych od długościokresu periodyczności. Oznacza to, że proponowany model, w przeciwieństwie do znanych modeli zhomogenizowanych, umożliwia badanie wpływu wielkości komórki periodyczności na wartości sił krytycznych w powłoce walcowej (wpływ ten zwany jest efektem skali). Wyprowadzony model porównano z modelem bez efektu skali i pokazano, że wpływ długości okresu periodyczności odgrywa znaczącą rolę w zgadnieniach stateczności periodycznie, gęsto użebrowanych powłok walcowych.

4

An experimental investigation of critical states of thin-walled structures with stiffeners subjected to constrained torsion

Kopecki T.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2002

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z. 58 [193]

163-168

EN

The results of experimental investigation of critical states of thin-walled open structures with different stiffeners, subjected to constrained torsion are presented in the paper. The tests were executed on the special steel models which complied with assumptions relative to stiffeners and boundary conditions. The purpose of the investigation was in order to obtain an information about buckling form of the structure and influence of kind of stringers (stiffeners) on the level of critical loads. Received results constituted the base to formulate very interesting conclusions, important from practical point of view.