Wyniki wyszukiwania - BazTech

1

Reaction of door constructions made of cellular wood material to fire

Spulle U., Bukšāns E., Iejavs J., Roziņš R.

Drewno : prace naukowe, doniesienia, komunikaty

|

2016

|

vol. 59, nr 198

171--179

EN

Cellular wood materials (hereinafter CWM) better known as Dendrolight® with their physical and mechanical properties are suitable for production of construction elements. A significant cost reduction, therefore, in transportation and mounting of the finished goods, as well as new and innovative modes of application based on the unique structure and lightness of the material, can all be achieved by developing the necessary technological and functional solutions. One of the possible building construction solutions are doors, including fire-resistant doors. This can be achieved by developing composites made of CWM and other materials that would meet the requirements set by building standards in terms of reaction to fire performance, fire resistance, and acoustics and developing CWM interconnection and fitting fastener solutions. The unique cellular structure ensures not only a reduced mass, but also a considerably better form stability under changing relative air humidity and temperature compared to materials used previously. During the research, initial tests were made to improve the reaction to fire properties of CWM by gluing it with some other materials. The results of the research showed that by gluing a CWM reference sample with 7 mm thick pine solid wood (longitudinal fiber direction) the charring and burn-through rates are the lowest compared to the other materials investigated. By reaction to fire performance specification, CWM with 7 mm thick pine solid wood, 4 mm thick MDF, or 6 mm thick MDF, gluing could be graded as class D in reaction to the fire classification system. The charring rate allows predictions of the potential fire resistance limit of door elements to be made. Assuming that the weakest spot in the construction is precisely the door elements, and of the materials tested, a 6 mm thick MDF or 6 mm thick magnesite panel was applied to both sides, CWM could be used to achieve EI 30 minutes fire resistance class limits.

2

Cellular wood material properties – review

Iejavs J., Spulle U.

Drewno : prace naukowe, doniesienia, komunikaty

|

2016

|

vol. 59, nr 198

5--18

EN

The invention of cellular wood material and lightweight furniture panels with the trade mark of Dendrolight® is just one of the wood industry’s innovations in the last decade. During the manufacturing process due to the sawn longitudinal grooves, solid timber becomes 40% lighter. Timber with grooves is a raw material for the cellular wood material production and furthermore is used for various sandwich panel designs. Since 2007 when cellular wood material production technology and furniture panels were patented, several researchers worked with experimental, analytical and numerical analysis of the cellular wood material properties for structural applications. This paper summarizes the main knowledge about the physical and mechanical properties of cellular wood materials and the possibilities for their potential improvement.

3

The comparison of properties of three-layer cellular material and wood-based panels

Iejavs J., Spulle U., Jakovl evs, V.

Drewno : prace naukowe, doniesienia, komunikaty

|

2011

|

vol. 54, nr 185

39-49

EN

In recent years a reduced weight cell panel, whose trade mark is Dendrolight, has gained worldwide recognition thanks to the opening of an experimental factory in Austria and the start-up of a new industrial factory in Latvia with manufacturing capacity of 65 thousand m3 cell board material per year. Hitherto the internal layer of cell panel of cellular wood material type has been produced mainly from softwoods like Norway spruce (Picea abies L.) or Scots pine (Pinus sylvestris L.) covered with plywood, solid wood, particleboard or other material. The reduced weight cell panel has many applications in the furniture industry, internal cladding, door production, the transport manufacturing industry, and possibly in the construction panel production. The essential goal of the research was to identify possible applications of aspen (Populus tremula L.) wood, which is a common broad-leaved tree in Latvia, as an alternative material to Norway spruce in the production of reduced weight cell panel. The aim of the initial research was to investigate some physical and mechanical properties of aspen cell panel covered with aspen and plywood as well as to compare these physical and mechanical properties with the properties of wood-based panels. The following raw materials were used: finger jointed aspen for internal layer; finger jointed aspen and three-layer birch plywood for external layer; polyurethane and polyvinylacetate adhesives for internal and external layer gluing. Tests of obtained aspen panel were carried out in accordance with current test standards for testing of panel and timber properties. The following panel parameters were determined: moisture content, density, swelling in thickness after 24-hour immersion in water, tensile strength, three-point bending strength and modulus of elasticity, and four-point bending strength. A relevant conclusion: panels of cellular wood material type produced from aspen wood have similar physical and mechanical properties to such cell panels produced from spruce wood.

PL

Płyty komórkowe o obniżonej gęstości mają szerokie zastosowanie w przemyśle meblarskim, wyposażeniu wnętrz, produkcji drzwi, środkach transportu. Mogą być również stosowane w wytwarzaniu płyt konstrukcyjnych. Założeniem badań było określenie przydatności drewna topoli (Populus tremula), rozpowszechnionego na Łotwie, jako substytutu drewna świerku, w produkcji płyt o obniżonej gęstości. W badaniach wykorzystano: drewno topoli na warstwę środkową, trzywarstwową sklejkę brzozową na warstwy zewnętrzne oraz kleje poliuretanowe i polioctanowinylowe. Zbadano następujące parametry wytworzonych płyt: gęstość, wilgotność, spęcznienie, wytrzymałość na rozciąganie, wytrzymałość na zginanie i moduł sprężystości. W podsumowaniu stwierdzono, iż płyty komórkowe wytworzone z drewna topoli charakteryzują się podobnymi właściwościami fizycznymi i mechanicznymi jak płyty komórkowe wytworzone z drewna świerku.