Tag Archives: wood

263-275 U. Spulle, E. Buksans, J. Iejavs and R. Rozins
Swelling Pressure and Form Stability of Cellular Wood Material
Abstract |

Swelling Pressure and Form Stability of Cellular Wood Material

U. Spulle¹*, E. Buksans¹², J. Iejavs² and R. Rozins¹

¹Latvia University of Life Sciences and Technologies, Forest faculty, Department of Wood Processing, Dobeles iela 41, LV-3001 Jelgava, Latvia
²Forest and Wood Products Research and Development Institute, Dobeles iela 41, LV-3001 Jelgava, Latvia
*Correspondence: uldis.spulle@llu.lv

Abstract:

Cellular Wood Material (hereinafter CWM) middle layer of the Dendrolight® has been developed in the beginning of this century as a wood material for minimization of internal stresses, because of the material structure and reduced swelling and shrinking impact to products in end use application. Some research has been conducted on the physical – mechanical and physical – chemical properties of CWM, while dimensional stability has not been well researched. The goal of this research is to perform an assessment of the CWM shrinkage and swelling impact on dimensional characteristics of the CWM multilayer composite materials. CWM swelling pressure in length, width, and height of the material were determined and compared to the relevant indicators of pine solid wood. The form stability or the impact of combination of the CWM with some facing materials – wood particle board, medium density fibre board (hereinafter MDF), oriented strand board (hereinafter OSB), pine solid wood, gypsum plaster board used in wood products was investigated. The hypothesis that swelling pressure of CWM must be lower than that of pine solid wood was proved, it is 2.3 times lower in the radial direction and 3.9 times lower in tangential direction compared to pine solid wood. The CWM samples, manufactured for determining the form stability in wetting conditions deflected in the height direction by 4%, thus creating deflections also in the seams between separate lamellas of the CWM. Swelling pressure of the CWM is several times smaller than that of solid wood and can be further limited by creating complex wood and non-wood composite material panels using gluing technique.

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313–321 M. Barbari, L. Conti, G. Rossi and S. Simonini
Supply of wood as environmental enrichment material to post-weaning piglets
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Supply of wood as environmental enrichment material to post-weaning piglets

M. Barbari*, L. Conti, G. Rossi and S. Simonini

Department of Agricultural, Food and Forestry Systems, University of Firenze, Via San Bonaventura 13, IT50145 Firenze, Italy
*Correspondence: matteo.barbari@unifi.it

Abstract:

Slatted flooring is a common system used for post-weaning of piglets. In this condition of breeding, it is very hard to provide materials for environmental enrichment to enable proper investigation and manipulation activities to improve animal welfare. The research aimed to identify an alternative way to provide natural environmental enrichment during post-weaning on slatted flooring using wood. Core of veneer poplar logs and wood sawdust pressed briquettes were selected among other types of wood thanks to their wide availability and low cost. Moreover, these kinds of wood can be used without compromising the health of the animals, neither by contact nor by ingestion. The most important step of the research was to design systems to make the wood more attractive for piglets. The developed devices consisted of a fixed structural component to be installed inside the pen to which wood materials could be added and replaced quite effortlessly. Three devices were developed: a) horizontal system, b) vertical system, c) pendulum system. They were tested in three different pens, each one with 24 post-weaning piglets. The results confirmed the assumption that there is a relation between the level of activity of the animals and the interaction with the wood proposed in the shape of small logs and briquettes. In particular the device a) can generate a valuable level of interaction of the animals reared inside the pen, especially in the first 10 days post-weaning, which is the most sensitive period for piglets after mixing.

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505-512 J. Papez and P. Kic
Wood moisture of rural timber constructions
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Wood moisture of rural timber constructions

J. Papez and P. Kic*

Czech University of Life Sciences Prague, Faculty of Engineering,Kamycka 129, 16521, Prague 6, Czech Republic;
*Correspondence: kic@tf.czu.cz

Abstract:

The aim of this paper is to present the methodology of measurement of moisturecontent of wood and show some results of this measurement in application on constructions ofagricultural buildings. Wood moisture can affect the durability of buildings. Measurements arein two different animal houses, which varied in design and implementation of the constructionmaterial (steel-wood and steel with wooden rafters). Both these buildings are relatively new(built in 2001 and 2009). There was measured also an older shed attached to the barn, which hasa storage and protective function. All these buildings are from spruce wood. The measurementwas based on the use of resistive sensor and capacitive sensor. Also determined was thetemperature and humidity of the air.From the results of measurements of tested buildings it is obvious that the moisture of the woodis in direct proportion with the relative humidity of the air. There are different results measuredby capacitive and resistive sensors. The suitability of the sensors for determination of woodmoisture was verified by gravimetric method, that is direct method and the results are veryaccurate. In the case of coniferous wood (especially spruce wood), there can be used withsufficient accuracy a capacitive sensor, which was used in all examined buildings. Key word: animal houses, wood, measurement, moisture content.

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