scholarly journals The Effect of Altitude Difference on Physical and Mechanical Properties of Scots Pine Wood Grown in Turkey - Sinop Province

2017 ◽  
Vol 67 (4) ◽  
pp. 393-397 ◽  
Author(s):  
Semih Esnaf ◽  
Deniz Aydemir
2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Przemysław Marcin Pikiński ◽  
Jaroslav Szaban ◽  
Gerda Šilingienė ◽  
Robert Korzeniewicz ◽  
Witold Pazdrowski

The aim of this study was to assess the quality of Scots pine (Pinus sylvestris L.) wood depending on the age of trees, forest site conditions and social class of tree position in the stand. Analyses were based on the determination of specific density and static bending strength, as well as the strength quality coefficient. It was to determine changes in physical and mechanical properties of timber depending on tree age as well as growth conditions reflected in the forest site such as fresh mixed coniferous forests and fresh mixed broadleaved forests. Experimental plots were established in 6 localities with 30, 40 and 60-year-old trees. In each of the stands, a 1-hectare experimental plot was established. Based on the measured DBH and tree height, dimensions of three mean sample trees were calculated, while the classification of social class of tree position in the stand developed by Kraft (1884) was also applied. Analyses were conducted on wood samples with 12% moisture content. Strength tests on wood samples were performed on an Instron 33RH204 universal strength testing machine. A detailed analysis showed properties of pine wood are improved with an increase of tree age in both forest sites. Statistically significant differences were observed for wood density and static bending strength. More advantageous properties were observed for wood of pines from the less fertile forest site, i.e., fresh mixed coniferous forests. Density and static bending strength were markedly determined by tree age and growth conditions. The static bending strength quality coefficient from pines growing in the fresh mixed coniferous forests increased between 30 and 40 years, similarly as it was for the fresh mixed broadleaved forests, while between 40 and 60 years, it deteriorated for the fresh mixed coniferous forests. Wood density from the fresh mixed coniferous forests was by 3% to 7% greater than pines growing in fresh mixed broadleaved forests. In turn, static bending strength of wood from pines growing in fresh mixed coniferous forests was by 4% to 10% greater than trees from the fresh mixed broadleaved forests.  Keywords: Scots pine, wood properties, forest site, Poland


2021 ◽  
Vol 113 ◽  
pp. 36-42
Author(s):  
Barbara Białowąs ◽  
Karol Szymanowski

Effect of thermomechanical densification of pine wood (Pinus sylvestris L.) on cutting forces and roughness during milling. The paper presents the results of research concerning the assessment of machinability of pine wood thermomechanically compacted. The assessment was made on the basis of the cutting forces and surface roughness after the milling process. Selected properties of native and modified wood were examined. Based on the research, it was found that compacted wood is characterized by higher cutting forces during milling. The surface quality after milling was examined and the roughness index Ra values were determined. The research shows that the modified wood is characterized by a lower Ra value both along and across the grain. Statistical analysis showed that the modification had a statistically significant effect on the values of cutting forces and the physical and mechanical properties of the tested wood.


Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1750 ◽  
Author(s):  
Radosław Mirski ◽  
Pavlo Bekhta ◽  
Dorota Dziurka

This study examined the effects of selected types of thermoplastics on the physical and mechanical properties of polymer-triticale boards. The investigated thermoplastics differed in their type (polypropylene (PP), polyethylene (PE), polystyrene (PS)), form (granulate, agglomerate) and origin (native, recycled). The resulting five-ply boards contained layers made from different materials (straw or pine wood) and featured different moisture contents (2%, 25%, and 7% for the face, middle, and core layers, respectively). Thermoplastics were added only to two external layers, where they substituted 30% of straw particles. This study demonstrated that, irrespective of their type, thermoplastics added to the face layers most favorably reduced the hydrophobic properties of the boards, i.e., thickness, swelling, and V100, by nearly 20%. The bending strength and modulus of elasticity were about 10% lower in the experimental boards than in the reference ones, but still within the limits set out in standard for P7 boards (20 N/mm2 according to EN 312).


1986 ◽  
Vol 18 (4) ◽  
pp. 259-262 ◽  
Author(s):  
William B. Banks ◽  
Gwynn Lloyd Jones

2021 ◽  
Vol 24 (2) ◽  
pp. 27-36
Author(s):  
Siarhei Rabko ◽  
Aliaksandr Kozel ◽  
Ivan Kimeichuk ◽  
Vasyl Yukhnovskyi

For a more efficient and rational use in the production of Scots pine wood of various geographical origin, it is necessary to know its physical and mechanical properties. The purpose of this study was to determine the physical and mechanical properties of wood of 17 climatic ecotypes of Scots pine and to carry out a comparative analysis of the indicators obtained for the studied climatypes separately and when they are grouped into subspecies in accordance with the classification of L.F. Pravdin. The range of the geographical origin of the places of seed procurement is from 47 to 62° north latitude and from 22 to 85° east longitude. The modern density universal testing machine MTS INSIGHT 100 was used for research. As a result of the research, it was found that the density of wood in an absolutely dry state varies from 370 kg/m3 (Kursk climatype) to 524 kg/m3 (Volgograd climatype), and at 12% humidity – from 397 kg/m3 (Kursk climatype) to 550 kg/m3 (Volgograd climatype). The index of the strength of wood of the studied climatypes for compression along the fibres was from 32 MPa (Kursk climatype) to 54 MPa (Volgograd climatype), and for static bending – from 55 to 92 MPa for the Vologda and Ulyanovsk climatypes, respectively. Distribution of Scots pine climatypes into subspecies in accordance with the classification of L.F. Pravdin and the obtained data on the physical and mechanical properties of wood have a certain pattern. The maximum density of wood at 12% moisture is typical for the European Scots pine subspecies is 497±8 kg/m3 , the minimum value of this indicator for the Siberian Scots pine subspecies is 423±30 kg/m3 . An intermediate position is occupied by the subspecies of Lapland pine and Forest-steppe pine with values of 483±16 and 464±12 kg/m3 , respectively. The strength index of wood in the studied subspecies for compression along the fibres ranged from 47±1 MPa (European subspecies) to 33±4 MPa (Siberian subspecies), in the Lapland pine subspecies – 44±2 MPa and somewhat lower in the Forest-steppe pine subspecies – 42±2 MPa. The maximum value of the static bending strength of wood is typical for the European pine subspecies – 78±4 MPa, and the minimum – for the Siberian pine subspecies – 61±14 MPa. This indicator turned out to be equal in subspecies of forest-steppe and Lapland pine and amounted to 72±4 MPa. The practical value of the work lies in identifying the existing differences and variability among climatypes according to the studied physical and mechanical properties of wood and selecting the most promising of them for further breeding purposes


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