Wyniki wyszukiwania - BazTech

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Numerical and analytical analysis of the stress- strain relations of extended beech plywood

Makowski A.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2014

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No. 88

136--142

EN

Numerical and analytical analysis of the stress- strain relations to extended beech plywood. The study presents a theoretical and numerical analysis of problems connected with the determination of strength parameters in multilayer beech plywood with varied layer configurations. Analytical calculations were performed in accordance with the classical theory of thin plates lamination in view of the theory of elasticity taking into consideration the Kirchhoff-Love hypothesis. The analyses focused on models of composite layers in plane stress. Values of components of transformed stiffness matrices were estimated theoretically together with those of flexibility in the axial and non-axial configurations of individual laminate layers. A verification was made of analytical calculation results with computer simulation results made on numerical models using the finite element method (FEM). Results of investigations are presented in the form of tables, graphs and graphic visualization of FEM calculations. Keywords: FEM calculations, lamina strength.

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Assessment of strength parameters of beech plywood in terms of failure criteria

Makowski A.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2014

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No. 88

143--146

EN

Assessment of strength parameters of beech plywood in terms of failure criteria. The failure state in a composite layer being in the complex state of stress is defined using the so-called material failure theories. They describe the yield surface of the material, for which the limit of linear elasticity is determined. Failure theories formulated for anisotropic materials are more complex. The paper presents the results of research on strength and deformation of the beech veneer during tension loading in relation to slope of grain. Results of the performed investigations were presented in the form of graphs end figures.

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Zastosowanie chromatografii gazowej do oznaczania wolnych monomerów i fotoinicjatorów w wykończeniach lakierowych na drewnie i materiałach drewnopochodnych

Witczak M., Komorowicz M., Wróblewska H.

Aparatura Badawcza i Dydaktyczna

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2012

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T. 17, nr 3

71-77

PL

Omawiana praca poświęcona była badaniom wykończonych powierzchni drewna i tworzyw drzewnych (mebli). Celem pracy było sprawdzenie przydatności metody chromatografii gazowej do oznaczania wolnych monomerów i fotoinicjatorów w pokryciach lakierowych utwardzonych promieniowaniem UV. Badaniami objęto drewno sosnowe oraz płyty HDF wykończone akrylowymi lakierami UV. Analiza zawartości wolnych monomerów wykazała, że w badanych materiałach nie zostało przekroczone dopuszczalne stężenie wolnych monomerów 800 mg/m2. Uzyskane rezultaty badań wskazują, że zastosowana metoda chromatografii gazowej jest odpowiednia do jakościowego i ilościowego oznaczania wolnych monomerów i fotoinicjatorów w pokryciach lakierowych UV. Otrzymane wyniki badań służą ocenie jakości i bezpieczeństwa gotowych wyrobów z drewna i tworzyw drzewnych.

EN

The presented research was dedicated to testing the finished surface of the wood and composite wood products (furniture). The aim of this study was to verify the suitability of gas chromatography method for determination of free monomers and photoinitiators for UV cured coatings. The study involved pine wood and HDF board finished with UV acrylic lacquer. Analysis of free monomers showed that in the investigated materials the permissible limit of 800 mg/m2 total concentration of free monomers are not exceeded. The obtained results show that the method of gas chromatography is suitable for qualitative and quantitative determination of free monomers and photoinitiators in paint coatings cured by UV radiation. Results of research serve to assess the quality and safety of finished products of wood and wood materials.