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给出了对中密度纤维板、胶合板等人造板材进行室外自然老化性能试验数据，即通过对放置在室外１￣２年的上述人造板材和各项物理力学性能的测试，进一步分析了室外自然老化对人造板材物理力学性能方面的影响及其产生原因，这项试验对今后人造板的生产与使用等方面，都具有十分重要意义。 相似文献
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简述了我国室外人造板产品发展概况及重要性能检测,从区域、性能检测和人造板种类三个方面比较分析了国内外对室外人造板重要性能的相关检测标准,阐述了我国现有室外人造板标准存在的不足,提出应尽快制定适合我国室外人造板产品的较为系统的检测方法标准体系。 相似文献
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介绍了气候老化因素对室外用木质人造板老化性的影响机理, 以及各种室内加速老化法在国内外的研究应用现状; 针对现行室内加速老化方法中存在的问题, 提出改进方法, 并对系统性加速老化方法的应用前景进行探讨。 相似文献
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本文统计检索了与竹质人造板相关的标准16个,其中包括3种基本类型竹质人造板:竹编胶合板,竹篾积成胶合板和竹材胶合板,简要分析了相应竹质人造板的生产工艺和技术参数,并比较3种基本类型竹质人造板强度差异。在此基础上,对竹质人造板标准化发展前景作出分析,主要涉及室内装饰装修材料系列国家标准对竹质人造板标准的影响,并在竹质人造板标准制订、修订和增加防火、防腐处理规定等方面提出建议。 相似文献
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本文论述了荷木(Schima superba)板材(厚25mm)热压干燥的试验研究。研究结果表明,采用热压干燥法可大大缩短阔叶树材的干燥时间,若板材的锯剖方法合理,干燥缺陷(如内裂)可显著降低,热板的压力对板材的厚度收缩有很大的影响。从整体考虑,热压干燥较佳工艺为干燥温度160℃,压力0.7N/mm~2。热压干燥法尤其适合于小规模手工艺木制品厂和雕刻木制品厂。 相似文献
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Effects of low bondability of acetylated fibers on mechanical properties and dimensional stability of fiberboard 总被引：1，自引：0，他引：1
Hideaki Korai 《Journal of Wood Science》2001,47(6):430-436
Fiberboards were prepared from acetylated fibers with various weight gains: 0, 4.7, 9.4, 18.5, and 24.8 weight percent gain (WPG). The effects of low bondability of acetylated fibers on mechanical properties and dimensional changes were determined. The decreased mechanical properties of acetylated fiberboard are mainly due to low bondability. To improve bending strength, high face density is also needed. The thickness swelling according to JIS and the linear expansion under relative humidity changes decreased with increasing WPG. As for accelerated weathering and the outdoor exposure test, the thickness changes in 4.7–18.5 WPG boards were much higher than those in OWPG board and 24.8 WPG board. The high thickness change in 4.7–18.5 WPG boards is due to low bondability. Although 24.8 WPG board also has low bondability, the thickness change of 24.8 WPG board decreased. The high dimensional stability of acetylated fibers, caused by high WPG, probably outweighs the dimensional change caused by low bondability. On the other hand, during the boiling test the thickness changes in 24.8 WPG board and the 4.7–18.5 WPG boards were higher than those in 0 WPG board. The effect of the boiling test on the boards is more severe than that seen with the accelerated weathering and outdoor exposure test; therefore, the effects of the low bondability probably cancel the effects of the high WPG. It is necessary to increase the bondability of acetylated fibers to improve the dimensional stability and the mechanical properties. 相似文献
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Ilze Irbe Juris Grinins Ingeborga Andersone Bruno Andersons 《Wood material science & engineering》2018,13(5):296-304
In this study, mould and blue stain susceptibility, capillary water uptake (CWU) and microstructural properties of two thermo-hydro-treated (THT) birch plywood products A and B were investigated. Plywood A represented a THT industrial plywood glued with a phenol formaldehyde (PF) adhesive. Plywood B represented panels from THT veneers glued with a PF film. The THT regimes were (temperature, °C/time, min): 150/10, 150/50, 160/10 and 160/50. Both THT plywood products and untreated samples were resistant to mould and blue stain growth in 1 month of exposure in laboratory and outdoor conditions. A statistically significant correlation between fungal growth in laboratory and outdoor conditions for plywood products A and B was not found (P?>?.05). Artificial weathering of both plywood products provided adverse fungal growth results compared to the natural weathering test outdoors. The fungal growth on plywood A and B samples mutually strongly correlated (P?相似文献
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1 INTRODUCTIONConservation of natural forests is a key issue in China’ssustainable rural development. One of the problems inrural China is the use of large quantities of wood andred bricks in house construction. This causesdestruction of forests, and the consequent watershortage and soil erosion problems.With the increase in living standards in rural areas,demand for housing is growing, and so is the demandfor high quality and attractive hotels for tourists.Moreover, many schools in Chi… 相似文献
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The durability of wood-based panels was evaluated by comparing the bending properties of panels subjected to five accelerated
aging treatments with the bending properties of panels that had experienced 5 years of outdoor exposure in Shizuoka City,
Japan. In each accelerated aging treatment, methylene diphenyl diisocyanate-bonded panels showed higher bending retention
than phenol formaldehyde (PF)-bonded panels. The bending retentions after six repeated cycles of the JIS-B, APA D-1, and ASTM
treatments showed a correspondence of nearly one-to-one in the data for the three different treatments. The Shizuoka City
5-year outdoor exposure test data showed that the bending retentions of all panels decreased with time. In particular, the
bending retentions of PF resin-bonded particleboard and oriented strandboard made from aspen were less than 30% and 10% of
the original values, respectively, after the 5-year exposure period. The deterioration of the bending properties after the
5-year outdoor exposure in Shizuoka City was the same as that for six repetitions of the ASTM treatment. 相似文献
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竹胶合梁制造及在建筑中的应用 总被引：12，自引：0，他引：12
在国际竹藤组织和中国林业科学研究院的技术支持下,第一所用竹材制作的云南省屏边小学校舍于2004年建成.它的校舍屋架,屋顶板和内外墙板均为竹集成材和竹胶合板制成.这使竹材从天然传统建筑材料向现代工程建筑材料转变,扩大了竹材在建筑领域的应用范围,对中国竹产业和建筑材料产业的发展将有积极深远影响. 相似文献
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The durability of wood-based panels is one of the most important properties when they are used in residential construction.
The main objectives of this study were to investigate the quantitative relationship between the Wet-bending A test and the
Wet-bending B test, examine the aging effects of the treatments specified in the wet-bending methods, and discuss the relationship
between wet-bending and outdoor aging tests conducted in Shizuoka, Japan. Wet-bending tests, internal bond tests after humidity
treatment, and outdoor aging tests in Shizuoka were conducted using eight types of commercial wood-based panels. A linear
relationship was found between the load-carrying capacity (LCC) from the Wet-bending A test and the LCC from the Wet-bending
B test. The LCC from Wet-bending B could be obtained from LCC from Wet-bending A by multiplying it by 0.9, which may be applicable
as a quantitative ratio of aging effects between the two. LCC for methylenediphenyl diisocyanate-bonded panels recovered to
almost 100% of the initial strength. A certain relationship was found between the LCC after Wet-bending A and the LCC after
a 1-year outdoor exposure in Shizuoka. Internal bond strength showed a good correlation between the JIS-A treatment and the
1-year outdoor exposure treatment. 相似文献
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An outdoor exposure test was conducted on kenaf core binderless boards (pressing temperatures 200°, 180°, and 160°C; pressing
pressure 3.0 MPa, time 10 min, target board thickness 5 mm, target board density 0.8 g/cm3) to estimate their bond durability. Modulus of rupture (MOR), modulus of elasticity (MOE), internal bonding strength (IB),
thickness change, weight loss, Fourier transform infrared (FTIR) spectra, and color difference (ΔE*) by the CIE L*a*b* system were measured at various outdoor exposure periods up to 19 months. These values were then compared with those of a
commercial medium-density fiberboard (MDF; melamine-urea-formaldehyde resin; thickness 9.0 mm, density 0.75 g/cm3). Generally, dimensional stability and the retention ratios of MOR, MOE, and IB after the outdoor exposure test increased
with increased pressing temperature of binderless boards. The MOR retention ratio of the kenaf core binderless boards with
a pressing temperature of 200°C was 59.5% after 12 months of outdoor exposure, which was slightly lower than that of the MDF
(75.6% after 11 months of outdoor exposure). Despite this, the bond durability of the kenaf core binderless boards should
be viewed as favorable, especially when considering the fact that the retention ratio of 59.5% was achieved without binder
and without obvious element loss.
Part of this report was presented at the International Symposium on Wood Science and Technology, IAWPS2005, November 27-30,
2005, Yokohama, Japan 相似文献
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Standard for Bamboo and its International Trend 总被引：1，自引：0，他引：1
WANG Zhaohui JIANG Zehui SUN QixiangResearch Institute of Wood Industry Chinese Academy of Forestry Beijing P.R. China 《中国林业科技(英文版)》2004,3(2):55-65
1 INTRODUCTIONNational forestry ecological engineering, as afundamental affair for environmental protectioncontains combating desertification, soil and waterconservation. Two measures might be taken to preventsoil and water losses. One measure is to enlarge theforest area and to stop cutting or to decrease cuttingforest so as to make forest coverage keep rising at astable speed, forest resources should be examined byremote sensing technology. The other is to control thecirculation of wood… 相似文献
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The deterioration of wood-based panels at eight sites in Japan over 7?years of outdoor exposure was investigated. In particular, the modulus of rupture (MOR) retention and internal bond strength (IB) retention after 7?years of exposure were compared among panels and sites. The deterioration of panels was greater in southern Japan than in northern Japan. The strength retentions in northern Japan decrease linearly, while those in southern Japan decreased exponentially. To quantify regional differences, deterioration rates were calculated based on three different weather conditions (precipitation, temperature, and sunlight hours), and the significance of each of these parameters on panel deterioration was determined. We found that the correlation coefficients between both IB and MOR retention and weathering intensity were the same whether we used 10-day, monthly, or daily weathering data. 相似文献