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1.
板式家具结构强度分析 总被引：6，自引：2，他引：6
50年代后期,Kotas对五面箱体的结构强度进行了研究,并且写了一本家具设计手册。Eckelman从板式部件的接合强度及家具的整体结构强度做了许多研究,他提出了板件的刚度与各种形式角接合变形的关系。他和Rabiej对带有横搁板和中隔板的柜体作了综合分析,得出计算公式,可用其计算三角固定一角自由条件下的柜体在受力时的变形。国内主要在家具力学性能测试方面,标准制定方面做了一些研究,在结构强度分析方面尚未进行过研究。 相似文献
2.
本文介绍了薄型刨花板的生产工艺和产品的性能与特点。就力学强度检测方法的改进和薄型刨花板的成本分析及应用前景阐述了看法。结合我国刨花板工业的具体情况,作者针对国内应如何发展薄型刨花板问题提出了建议。 相似文献
3.
Richard Wascher Christian Kühn Georg Avramidis Sascha Bicke Holger Militz Gisela Ohms Wolfgang Viöl 《Journal of Wood Science》2017,63(4):338-349
This study investigates the dimensional stability and mechanical properties of plywood boards made of thermally modified and unmodified beech veneers that have undergone plasma pre-treatment before melamine resin impregnation. The water and melamine resin uptake and resulting weight percent gain of the veneers were investigated, whereby the air plasma pre-treated veneers showed improved liquid uptake. Five-layer plywood boards were then manufactured and tested for their dimensional stability, compressive strength, bending strength, and tensile strength. Plywood boards made of thermally modified and plasma pre-treated veneers showed a significantly improved dimensional stability, along with small influences on their mechanical properties. 相似文献
4.
Wood-based panels are subjected to cyclic panel shear load caused by wind and seismic forces in such an application as the sheathing of bearing walls. The fatigue behavior of structural plywood under panel shear load with two different loading frequencies was examined. Pulsating panel shear load with a triangular waveform and loading frequency of 0.5 or 5 Hz was applied to the plywood specimens. Stress−strain hysteresis loops were measured throughout the fatigue tests. Fatigue life was highly dependent on loading frequency at more than 0.5 stress level. The deterioration of mechanical property and damage accumulation in plywood specimen was observed to be slower at higher loading frequency at more than 0.5 stress level. Analyses based on energy loss suggest that panel shear load with higher loading frequency causes less damage to the plywood specimen during one loading cycle at higher stress level, and that the fatigue damage accumulation causing failure might be dependent on stress level although it seems to be unaffected by loading frequency. Based on these results, a new fatigue failure model for plywood specimen was qualitatively developed by combining Weibull’s weakest link model and Daniels’ fiber bundle model. 相似文献
5.
Okumu Gordon Wanyama Kei Sawata Takuro Hirai Akio Koizumi Yoshihisa Sasaki 《Journal of Wood Science》2012,58(4):315-321
In this study, an experimental study was conducted on the nailed timber–plywood–timber joints extended from the standard wall–floor joints of wooden light frame constructions, where the bottom plates of shear walls are nailed to the floors consisting of joists and floor sheathings nailed to them. The principal conclusions are as follows: The allowable lateral resistance of the nailed timber–plywood–timber joints can roundly be estimated by neglecting the plywood panels if their densities are higher than those of the timber main-members and they are fastened effectively onto the timber main-members. The stiffness of the timber–plywood–timber joints is less than that of the control timber–timber joints, which is improved by increasing the number of nails used to fasten the plywood panels onto the timber main-members. The stiffness of the joints whose floor sheathings are glued onto the joists is equivalent to the control timber–timber joints. The timber–plywood–timber joints with appropriate specifications have greater energy capacity until the failure than that of the control timber–timber joints. This ensures their energy capacity, which is important in dynamic resistance, to be equivalent to the control timber–timber joints. 相似文献
6.
柜类家具在地震中产生震害的危害性大。在我国引起家具震害的中小地震频发,但家具震害的相关研究较少。对柜类家具在地震作用下的摇晃现象进行运动理论分析,运用数值模拟研究方法结合柜体倾翻试验,对影响地震中柜体倾翻的自身因素进行研究,用于后续指导柜类家具的防倾翻设计。结果表明:在相同地震力大小的条件下,柜体倾翻的时间会受到柜体重心深度和高度变化的影响。当地震力大小不足以克服柜脚与地面间的摩擦力时,柜体重心的深度和高度是影响柜体倾翻的主要因素;柜体倾翻时间与柜体重心的深度成正比,与柜体重心的高度成反比;当柜体深高比相同时,倾翻时间与柜体侧面体量成正比;柜体倾翻试验验证了数值模拟研究方法,具有可行性和可靠性,可用于后续柜类家具安全尺寸的设计。 相似文献
7.
美式木制柜类家具的基本结构(Ⅰ) 总被引：1，自引：1，他引：0
结合图片和实样,对美式木制柜类家具的用材、设计、结构进行了探讨,主要分析了柜类家具的面板、顶板、旁板、背板、框架(包括前框、层框、后框)、抽屉及门的结构. 相似文献
8.
Fire resistance of thick wood-based boards 总被引：1，自引：0，他引：1
Thick wood-based boards are used as construction materials for walls and floors in Japan. In this study, fire resistance tests
(ISO 834-1) and cone calorimeter tests (ISO 5660-1) were conducted for thick plywood, particleboard, and medium density fiberboard
with sample thicknesses of about 28–30mm, and their suitabilities for quasi-fireproof or fire-preventive structures were evaluated.
In the ISO 834-1 fire resistance test, the heat-shielding performance (insulation criterion) for walls was evaluated and the
results showed that the larger the apparent density of a woodbased board, the higher its insulation performance. The insulation
performance of thick wood-based boards in the fire resistance test could be forecast from the results of the cone calorimeter
test, especially when the second peak of heat release rate appeared. In the cone calorimeter tests, the surface layer density
of the plywood, particleboard, and medium density fiberboard was the dominant parameter for the time to ignition and initial
heat release rate. These results indicate that thick wood-based board is a suitable fire-preventive construction material.
Part of this study was presented at the Annual Meeting of the Architectural Institute of Japan, Hokkaido, Japan, August 2004 相似文献
9.
采用单因素法分析了分子筛类型及用量对磷氮阻燃剂浸渍杨木单板制备的胶合板的阻燃性能和胶合性能的影响。研究结果表明:分子筛在磷氮阻燃胶合板中显示出良好的协效阻燃作用。加入量为1%时就能够显著提高阻燃胶合板的阻燃性能,不同类型分子筛对阻燃性能的提高程度依次为4A>5A>13X>3A;分子筛在协效阻燃的同时,还可以提高阻燃胶合板的胶合强度。分子筛加入量为3%时阻燃胶合板的胶合强度提高最大,各类型分子筛对胶合强度的提高程度依次为13X>5A>4A>3A。 相似文献
10.
以橱柜待装RTA家具为例,介绍利用面向对象的设计思想构建RTA家具CAD模型类的方法,建立单元柜的类初始化和对象引用关系. 相似文献
11.
采用废弃一次性筷子和胶合板单板制备复合板,对其制备工艺进行了初步研究。试验制备的三层和五层结构复合板性能均可达到细木工板的标准要求。Abstract： One-off chopsticks and veneer plywood are used to make composite boards,and the preliminary study is made of the manufacturing process.The performance of three-layer and five-layer composite boards made during the experiment has reached the standard requi 相似文献
12.
This study investigated the effects of mild steam treatment (0.1 MPa for 2 h) of natural bio-based fibers and orientation
(0° and 90°) of those fibers in various fiberboards. Ramie bast, pineapple leaf, and sansevieria fiber bundles were used as
materials. The composite fiberboards were prepared using phenol-formaldehyde (PF) resin. To investigate the effect of mild
steam treatment on wettability, contact angles of PF resin to the fiber were measured. The mechanical properties of the boards
were examined as well as their dimensional stability. The contact angle data showed that mild steam treatment was effective
in improving the wettability of fibers. Unioriented steam-treated boards showed better performance of internal bond (IB),
moduli of rupture (MOR) and elasticity (MOE), thickness swelling (TS), and water absorption (WA) than other boards. Unioriented
steam-treated sansevieria board with longitudinal fiber direction showed higher average values of MOR (403 MPa), MOE (39.2
GPa), and IB (1.33 MPa) and lower values of TS (5.15%) and WA (8.68%) than other boards. The differences in the mechanical
properties and dimensional stability of boards were found mainly due to the differences in the ratios of fiber fraction of
the boards to the density of the fiber bundles. 相似文献
13.
竹材通过加工制成的竹质人造板,不仅大量用作代木材料,而且有的竹质板力学强度很大,非木材所能比拟,是良好的工程结构材料。发展竹质板生产是克服木材短缺的切实有效途径。目前浙江竹质人造板主要种类有:竹材胶合板、竹编胶合板、竹篾胶合板、竹丝胶合板和竹材旋切片(板)五种。文章介绍了上述五种板的工艺流程、板的物理力学性质、主要用途,生产中存在的问题以及可供借鉴的国内外先进技术。 相似文献
14.
本文对用喷砂处理的竹片作表层材料、芯层用木刨花制成的复合胶合板作了研究,结果表明复合胶合板具有非常高的强度,生产中可采用先将竹片和木单板胶合成一片,再将其和木刨花一次复合成板的工艺。 相似文献
15.
快递包装是一种数量大、回收率低的特殊包装材料,在包装过程中各类材料的重叠使用,不利于后期的回收利用。通过当前再生材料用于家具制造的相关理念和工艺特征的分析,以及快递包装所用材料的数量及相互关联性的调研,提出了简化快递包装回收分类以用作板式家具用材的构想。针对板式家具用材特点,总结出原材料所带来的污染是制约板式家具发展的主要"瓶颈",在满足用户、企业、国家政策三方面要求的前提下,确定了以材料为导向的板式家具用材开发策略,并提出了几种利用回收快递包装材料制板的构想。 相似文献
16.
B. Ozarska 《Wood Science and Technology》1999,33(4):341-351
This review on the use of hardwoods for the production of LVL revealed that a large number of research studies have been
carried out, particularly in North America and three Asian countries (Japan, Malaysia and China). However, the studies have
been restricted to species of low to medium density, i.e. 290 to 693 kg/m3. Two major potential uses of hardwood LVL have been investigated in these studies: domestic and industrial structures, and
various furniture components. The production of structural LVL in North America and Asia was based predominantly on low density
hardwoods. A study currently carried out in Europe aims at using medium density hardwoods for structural LVL. The LVL used
for furniture components was produced from medium density hardwoods. No work has been undertaken outside Australia on the
use of high density species for LVL. In Australia, studies undertaken on the production of LVL and hardwood plywood from eucalypts
revealed that there were significant problems in gluing the dense raw material which often had a high level of extractives.
Peeling low quality, small diameter eucalypt logs also created problems when the traditional plywood processing techniques
were used.
Received 7 July 1997 相似文献
17.
Binderless particleboards were manufactured from sugi (Cryptomeria japonica D. Don) heartwood and sapwood by hot-pressing (pressure: 5 MPa; temperatures: 180°, 200°, and 220°C; times: 10, 20, and 30
min), and the board properties [internal bonding (IB), thickness swelling (TS), water absorption (WA)] were investigated to
evaluate the self-bonding ability. The IB, TS, and WA of the boards from sugi heartwood were better than those of the boards
from sugi sapwood at any hot-pressing condition. Therefore, it was suggested that the self-bonding ability of sugi heartwood
was superior to that of sugi sapwood. Then, sugi heartwood and sapwood powder with grain size 10 βm were used as a binder
for plywoods. Four kinds of plywood were manufactured from the combination of powder and veneer, both of which were prepared
from sugi heartwood and sapwood under the same hot-pressing conditions as the binderless particleboard, and the adhesive shear
strength and wood failure of the plywood were investigated. As a result, the plywood composed of sugi heartwood veneer met
the second grade of JAS for plywood, when either powder was used as a binder, when they were pressed at 200°C for 20–30 min
and 220°C for 10 min. 相似文献
18.
Summary A detailed study of the growth stresses and strains in the cork shell of the cork-oak was undertaken based on experimentally determined constitutive relations for cork in tension and compression. The stresses depend on the thicknesses of the cork shell and of the back layer around the cork shell, on the radius of the trunk and on its increase due to growth. The circumferential stresses in the cork shell and back layer are tensile and increase with increasing distance to the tree axis. The radial stresses are compressive and decrease with increasing distance to the tree axis. The strains due to growth are not recovered when the cork boards are removed, unless the boards are heated, for example, by immersion in boiling water. Other consequences of the growth stresses are analysed, such as the occurrence of corrugations in the lateral cell walls of cork, the variation of width of the successive growth rings and the occurrence of cracks in the back layer and outer cork layers. 相似文献
19.
There is a growing desire to improve the properties and use of nonwood plant materials as supplements to wood materials for wood cement-bonded boards (WCBs). This study was conducted to determine the comparative properties of WCBs containing various amounts of discontinuous inorganic fiber materials, such as alkali-resistant glass fiber, normal glass fiber, mineral wool, and nonwood plant materials such as retted flax straw and wheat straw particles. Tested cement-bonded boards were made at wood/additive compositions of 100/0, 90/10, 80/20, 70/30, 60/40, and 50/50 (weight percentages). Seventy-eight laboratory-scale WCBs were produced. Various board properties, such as the modulus of rupture (MOR), internal bonding strength (IB), water absorption (WA), thickness swelling (TS), and linear expansion (LE), were studied. The test results showed that three types of discontinuous inorganic fiber used as reinforcing materials in composites significantly enhanced and modified the performance of WCBs. The mechanical properties and dimensional stability of cement-bonded board were significantly improved with increasing amounts of the additives. MOR and IB were increased; and WA, TS, and LE of boards were reduced by combination with the inorganic fiber materials. The results also indicated that combination with retted flax straw particles only slightly increased the MOR of boards, and wheat straw particles led to marked decreases in all the mechanical properties and the dimensional stability of WCBs.Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000 相似文献