Wyniki wyszukiwania - BazTech

1

Membranowe przekrycia dachowe Część 2 – detale konstrukcyjne

Pańtak M.

Builder

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2016

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R.20, nr 4

75--79

PL

Detale konstrukcyjne stanowią w zadaszeniu elementy kluczowe, niejednokrotnie decydujące o właściwej i bezpiecznej pracy oraz eksploatacji zadaszenia, jego trwałości i kosztach budowy.

EN

The article presents the design process of lightweight membrane roofs made of technical fabrics. Main emphasis in the second part of the article has been put on construction details usually being key in the design, as correct and safe work and use of the roof, as well as the cost and durability depends on them.

2

Niekonwencjonalne konstrukcje silosów do składowania biomasy

Hotała E., Kuśnierek M., Aniszczyk A., Pawłowski K.

Materiały Budowlane

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2014

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nr 5

53--55

PL

W artykule zaprezentowano niekonwencjonalne konstrukcje do składowania zbrylających się materiałów, do których należy również biomasa. Konstrukcje te opracowano na podstawie wyników badań silosów walcowych o podatnych i wiotkich płaszczach. Przedstawiono konstrukcje podatnych walcowych powłok płaszczy silosów z nieużebrowanych blach falistych, które ułatwiają przepływ materiału w kierunku ich płaskich den podczas ich opróżniania. Najlepsze efekty w uzyskiwaniu przepływu masowego podczas opróżniania uzyskano w silosach o wiotkich, tkaninowych płaszczach walcowych.

EN

The unconventional constructions for selfprilling materials e.g., biomass have been presented herein. The constructions have been developed on the base of research results obtained for cylindrical siloses having a flexible and flabby shells.A cylindrical flexible silos shells from unribbed corrugated sheets , in which the flow of materials towards the silo flat bottom is facilitated have been presented. The best effect of the mass flow efficiency have been reached in cylindrical silos with flabby shells.

3

Experimental Research on Technical Fabric of the Forest Opera Roof in Sopot

Żerdzicki K., Kłosowski P., Woźnica K.

Machine Dynamics Research

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2012

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Vol. 36, No. 2

118-126

EN

The experimental analysis of the technical fabric Valmex is presented. The study involves uniaxial tensile, cyclic, rheological and biaxial tests. Some of the main differencies between two types of the analysed material have been identified. Mechanical properties of the textile have been modeled by the viscoelastic standard model with quite good effect.

4

Rheological Properties of Technical Fabric

Komar W., Kłosowski P., Woźnica K.

Machine Dynamics Problems

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2008

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Vol. 32, No. 2

24-37

EN

This work presents a brief results comparison of two different attempts at the nonlinear characteristics of the same textile "Panama", manufactured by Sattler Company (Germany). On the basis of uniaxial tension and creep-recovery laboratory tests the rheological properties of technical fabric were identified. To describe material's nonlinear behaviour in its inelastic range constitutive relations of viscoplasticity and viscoelasticity were applied. The same procedure of the parameters identification, using the least squares method in the Levenberg-Marquardt variant, was conducted in each theory. Calculations were carried out for warp and weft threads individually, that is in two perpendicular directions of the material's weaving. Identification results were verified and compared to the experiments. Both nonlinear model representations advantageously approximate the tests' data of the examined technical fabric.

5

Identification of Nonlinear Viscoelastic Properties of the "Panama" Fabric

Komar W., Kłosowski P., Woźnica K.

Machine Dynamics Problems

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2006

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Vol. 30, No. 2

63-70

EN

Technical fabric "Panama", manufactured by Sattler Company (Germany), exhibits some nonlinear behaviour including the viscoelastic effects, during the long-term experiments. On the basis of uniaxial creep-recovery laboratory tests, conducted for five different stress levels from 10% to 50% of the ultimate force declared by the producer, an attempt on the nonlinear viscoelastic identification of the fabric properties was made. The Schapery one-integral model of nonlinear viscoelasticity was applied as the constitutive relation, describing material's behaviour in inelastic range. The power law time function was assumed to represent the transient component of the linear creep compliance. For each stress level the same procedure of the parameters identification was conducted, using the least squares method in the Levenberg-Marquardt variant. As the considered material has two thread families, warp and weft, weaved perpendicularly one to another, calculations were carried out for each thread direction individually. Results of the identification were verified and compared to the experiments' data. Good agreement between the nonlinear model representation and the tests' data of the examined technical fabric was obtained. Some remarks upon further research were included.

6

Charakterystyka tkaniny technicznej "Panama" w zakresie lepkosprężystym

Komar W.

Biuletyn Wojskowej Akademii Technicznej

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2006

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Vol. 55, nr 4

267-281

PL

Niniejszy artykuł zawiera część prac nad pełnym scharakteryzowaniem tkanin technicznych. Obiektem zainteresowania jest tkanina techniczna "Panama" firmy Sattler. Autor postawił sobie za cel zidentyfikowanie parametrów wybranych lepkosprężystych modeli konstytutywnych materiałów oraz ich weryfikację na podstawie prób jednoosiowego rozciągania ze stałą prędkością odkształcenia. Zaprezentowano dwa wybrane do identyfikacji modele lepkosprężyste, z których jeden jest reprezentowany liniowym równaniem różniczkowym, a drugi - nieliniową zależnością całkową. Dokonano zestawienia otrzymanych wyników z przeprowadzonej już części identyfikacji. Zaproponowano metodę ulepszającą proces identyfikacji parametrów modelu standardowego dla materiałów o charakterystykach nieliniowych. Przedstawiono aktualny stan prac nad identyfikacją kierunki dalszych badań.

EN

Technical fabrics are more often used in different industry interests. Mainly in the civil engineering structures like hanging roofs or pneumatic stores, but also as the road structures reinforcement or transporting belts. The subjected textile, considered in this paper is the technical fabric "Panama", manufactured by Sattler company (Germany). It has two identical polyester thread families: warp and weft of P2/2 weaving with double side PVC coating. Despite the anisotropy of that fabric, it has been assumed that its threads were made of the isotropic material. The research presented here is concerned with the identification of the "Panama" fabric behaviour, for each thread family separately, using the constitutive relations of linear and nonlinear viscoelasticity. The research is based on the laboratory tests of uniaxial tension with the constant strain rate. Tests were conducted for five different strain rate levels from 10⁻⁵ ; till 1.67×10⁻³ ; [1/s]. For linear representation of the examined material, the three-parameter model of viscoelastic solid was applied in a form of the differential equation, and the one-integral relation of the Schapery model was assumed to describe the nonlinear viscoelasticity of examined material. Models selected for further examination were presented more precisely. The identification process based on the linear standard model was conducted using the least squares method in the Marquardt-Levenberg variant. The calculated parameters were subsequently verified and the results were compared to the experiments. As it soon turned out, some problems with parameters determination occurred, and it was necessary to modify the linear viscoelastic model, to make it able to describe the "Panama" behaviour with reference to the tension tests. The proposed modification method was presented in the paper and improved results of material's description were compared to the experiments. Some negative aspects of the identification procedure were finally pointed out, and the next steps in the research schedule were suggested, to tend towards the main aim of this investigation, that is the entire viscoelastic characterization of the "Panama" fabric.

7

Physical parameters' identification for technical fabrics - viscoelastic mode

Komar W.

Zeszyty Naukowe. Budownictwo / Politechnika Śląska

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2003

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z. 101

191-198

EN

Practical application of technical fabrics for construction requires the knowledge of their physical properties. The constitutive models of material, particularly viscoelastic models of solid, have the essential use here. Two models have been selected (the linear standard model and its non-linear variation) and their constitutive equations have been written in one-dimensional case. Laboratory tests of uniaxial tension constant strain rate have been conducted, and the inelastic effect have been observed during them. The least squares method has been chosen for the models' parameters identification and also the fabric model - the dense net model have been chosen for further applications.

PL

Praktyczne wykorzystanie tkanin technicznych w konstruowaniu wymaga znajomości ich własności fizycznych. Konstytutywne modele materiału mają tu zasadnicze zastosowanie, a w szczególności modele lepkosprężyste ciała stałego. Spośród wielu znanych modeli wybrano dwa (liniowy model standardowy i jego wariant nieliniowy) i zapisano ich równania konstytutywne w układzie jednowymiarowym. Przeprowadzono badania laboratoryjne jednoosiowego rozciągania ze stałą prędkością odkształcenia, podczas których zaobserwowano efekt niesprężysty. Do identyfikacji parametrów modeli wybrano metodę najmniejszych kwadratów, a jako model samej tkaniny do dalszych zastosowań - model sieci gęstej.