异氰酸酯定向结构板的蠕变特性

异氰酸酯胶粘剂以不含甲醛的独特优点被人们举荐用于定向结构板的生产。对主要作为承重材料的定向板来说,除了对类似普通刨花板的基本物理力学性能有一定的要求外,还希望板材具有理想的抗蠕变性能。为了考察异氰酸酯定向结构板的蠕变特性,特在实验室内进行了本项试验。     

异氰酸酯定向结构板试验

在实验室内压制异氰酸酯定向结构板,研究用胶量和板子密度对物理力学性能的影响。结果表明,异氰酸酯作为制造定向结构板的胶粘剂具有许多独特的优点。     

定向结构板复合墙体热特性的评价

文中运用有限差分法和积分变换法评价定向结构板复合墙体的热特性,并将之与传统的砖混结构进行了比较。研究结果表明,建筑物的室内热环境状况主要取决于转护结构的组成材料和构造;定向结构板复合墙体的透过热稳定性好,其对外界扰量（室外气温）的衰减倍数约是砖墙的７￣８倍;比普通粘土砖墙厚度减小一半的定向结构板和玻璃棉板复合墙体对外扰的减弱能力仍大于普通粘土砖墙;大空间范围（如体育馆、影剧院、商店等）,采用轻质木质复合材料作内装修,将有利于空凋设备地室内空气温度的调节。     

定向结构板的特殊处理定向结构板系列讲座之四

定向结构板的特殊处理定向结构板系列讲座之四南京林业大学定向结构板工程研究中心１概述定向结构板以其特有的用途（比如建筑、车船制造和混凝土模板等）要求产品具有相应的特性，归纳起来有四，即阻燃特性、低甲醛释放特性、耐久性和尺寸稳定性。按照正常工艺制造的定向...     

刨花长度及板坯铺装结构对麦秸板性能的影响

以长秸秆刨花、短秸秆刨花为原料,分别制备单层定向、三层定向和非定向等三种不同铺装结构的秸秆刨花板,研究刨花长度与板坯铺装结构对麦秸板性能的影响。结果表明,按本试验设定工艺参数制备的试板,性能均可达到LY/T 2141-2013《定向结构麦秸板》干状承载型板材的要求。实际生产中,可依据目标产品的应用领域,选择适宜的刨花长度和板坯结构。     

定向结构板内水蒸气稳态扩散系数的研究

采用扩散杯法研究了定向结构板内水蒸气稳态扩散系数。结果表明，定向结构板内平行于板面的水蒸气稳态扩散系数约是垂直于板面的水蒸气稳态扩散系数的１０倍左右。定向结构板内水蒸气稳态扩散系数随着板密度的增加而减小，并且与密度成二次函数关系。     

定向结构板推广前景与经济分析定向结构板系列讲座之六

定向结构板推广前景与经济分析定向结构板系列讲座之六南京林业大学定向结构板工程研究中心１概述定向结构板作为一种新型结构材料能否在我国得到稳定的发展，主要取决于以下因素：①在日益激烈的市场竞争中，产品的应用范围能否定位并展现独特的优势；②产品的性能和质量...     

冷杉木材与不同覆板材料钉连接节点的动态荷载性能研究

钉连接是木结构中重要的连接节点,在轻型木结构建筑的剪力墙中起到重要的承载作用。不论国内还是国外,结构胶合板、定向刨花板、冷杉木材都是木结构建筑中主要的建筑材料。笔者研究了不同覆板类型与冷杉木材钉连接的动态荷载性能,对不同厚度胶合板、定向刨花板、钉直径与冷杉的连接性能进行了对比(静态荷载和动态荷载)研究。结果表明,钉直径、覆板种类和厚度对动态载荷性能、破坏位移影响显著,10D钉连接冷杉和不同覆板材料时,连接性能最佳;相同厚度的定向刨花板比结构胶合板与冷杉的连接性能好;厚度为16 mm的结构胶合板具有良好的连接性能。本研究为轻型木结构的建造提供理论和实际测试依据。     

塑化定向结构板的研制

用低浓度低分子量的ＰＦ胶的浸胶工艺，以常规工艺（热进热出工艺）和特殊工艺（冷进冷出工艺）两种方法生产ＯＳＢ板，这些板称为塑化定向结构板；比较了这两种ＯＳＢ板的物理力学性能上的差异，采用二次正交数学模型，得出两种方法的最优工艺参数，以提高ＯＳＢ的综合性能指标，扩嵈笃溆τ梅段А     

竹木复合定向刨花板强度性能研究

本文论述了竹材、意大利杨复合定向刨花板的强度性能,就胶种、刨花厚度、竹材所占比率、板密度、板坯结构、施胶量等诸因子对板材强度性能的影响进行了探讨。结果表明:(1)胶种对竹木复合定向刨花板的强度影响不大;(2)降低刨花厚度或提高板密度均可使板材强度提高;(3)单层结构的复合定向刨花板强度最高;(4)提高板材中竹材的比率可使板子强度明显改善;但竹材比率过高时,板材强重比反而下降,呈开口向下的抛物线型变化;(5)酚醛树脂定向刨花板的强度随原料酸性增大而降低。     

Effect of two relative humidity environments on the performance properties of MDF, OSB and chipboard.

The fatigue and creep performance of MDF, OSB and chipboard have been examined in two environments, namely 65%RH (standard environment) and 85%RH (high humidity). Parallel fatigue and creep tests have been performed in four-point bending on the three wood-based panel products in the two environments. The constant 65%RH environment is service class 1 and the constant 85% RH environment is indicative of a service class 2 environment as detailed in Eurocode 5. The non-interruptive technique of stress-strain hysteresis loop capture has been utilised to follow property changes of the fatigue samples during cyclic loading at a stress ratio of R equal to 0.1. Loop parameters such as loop area, dynamic modulus, and fatigue modulus have been used to characterise the response of these materials to fatigue loads in the two environments. Creep microstrains for the creep samples were recorded in parallel with the fatigue parameters. Fatigue and creep results at 85%RH were more variable than those reported at 65%RH for MDF, OSB and chipboard. In general, at R=0.1 and 85%RH, fatigue and creep microstrains were higher, dynamic stiffnesses were lower and hysteresis loop areas were higher than corresponding properties measured at 65%RH. MDF and chipboard were less moisture tolerant than OSB, this is reflected in the large changes in fatigue and creep parameters.     

Effect of two relative humidity environments on the performance properties of MDF, OSB and chipboard

The static strength, stiffness and fatigue life of MDF, OSB and chipboard have been measured in a 65%RH environment and a 85%RH environment. Chipboard is commonly utilised as a flooring material and OSB is also used in structural applications, for example floor decking and webs of I-beams. The mean static strengths of MDF, OSB and chipboard at 65%RH were 47.9 MPa, 27.9 MPa and 21.0Mpa, respectively, compared with 34.59 MPa, 21.70 MPa and 10.61 MPa at 85%RH. However, MDF has mostly been used in non-structural applications, such as furniture, so its resistance to fatigue loads as a structural panel is of considerable interest. In a 65%RH environment dynamic modulus values showed that whilst MDF and chipboard exhibit similar stiffness values (4 GPa), OSB is approximately 50% stiffer. However, at 85%RH MDF was the stiffest of the three materials, followed by OSB and chipboard. The fatigue life performance of all three panel products was markedly lower at 85%RH compared with 65%RH. Overall, the high RH environment had a noticeably detrimental effect on the MOE (modulus of elasticity), MOR (modulus of rupture) and fatigue lives of OSB and chipboard. This is attributed to these panels retaining more of the original characteristics of the original wood, i.e. larger particle sizes (flakes/chips) compared with the homogeneous fibrous composition of MDF. Received 5 November 1999     

Fatigue in wood-based panels. Part 2: property changes during fatigue cycling of OSB, chipboard and MDF

Wood-based panels are viscoelastic so when a load (stress) is applied to them there is a time lag before a deflection (strain) is produced, which results in hysteresis (a loss of energy). The capture of stress versus strain hysteresis loops is a non-interruptive method of monitoring the damage produced during fatigue testing. Hysteresis loops were captured throughout the flexural fatigue testing of OSB, chipboard and MDF in four-point bending allowing the development of fatigue damage to be followed. The MDF tested had a greater mean bending strength than the OSB and chipboard. When stresses were applied to the materials as a percentage of their bending strengths, the stresses applied to the MDF samples were larger than those applied to the OSB and chipboard samples. As a result the microstrains were greater for MDF than for the chipboard and OSB. The OSB was stiffer than the chipboard and MDF, which were both of similar stiffness. The information gained from the hysteresis loops indicates that the OSB, chipboard and MDF all had fatigue limits just below 20% of their bending strengths. The fatigue limit for the MDF is likely to be slightly lower than for the chipboard and the OSB.     

定向结构板居室室内热环境的研究

运用温湿度自动记录仪对3种不同结构实体建筑的室内垂直空间的温湿度，墙体内外表面温度进行了监测，分析了建筑物的日平均温度变动比、衰减倍数。墙体内外表面以及室内垂直空间的温湿度分布，研究结果表明，内外表面均采用定向结构板，中间填充玻璃棉的复合墙体比传统砖墙的保温隔热性能好，能有效地抵抗外界大气环境对室内热环境影响的作用。     

水杉脲醛树脂胶定向刨花板的研究

利用水杉木材制造定向刨花板（ＯＳＢ），既是水杉高效利用的途径之一，又为ＯＳＢ拓展了原材料来源，为ＯＳＢ的发展提供了条件，本文分析了水杉木材与制板工艺有关的物理，力学，化学性质，研究了水杉材ＵＦ胶ＯＳＢ的生产工艺，试验结果表明，利用水杉木材生产ＵＦ胶ＯＳＢ是完全可行的，只要工艺参数选择合理，产品性能可达或过欧共体ＵＦ胶定向刨花板标准要求。     

我国定向结构刨花板的现状和发展前景

本文介绍了定向结构刨花板的性能、用途和国内外发展的状况,提出了在我国发展定向结构刨花板应解决的几个问题,指出不论从人造板的发展趋势,还是从保护生态环境,发展迷生人工林培育与利用的可持续发展策略上看,定向结构刨花板作为新型的人造板在我国必将有巨大的发展潜力。     

彩色定向结构刨花板的研制

彩色定向结构刨花板（ＯＳＢ）是利用染我后的大片刨花为表层,本色刨花为芯层,施 后一次热压成型,经简单处理后用于有色彩要求的场所。本研究主要探讨染色工艺对刨花表面相对自由基浓度的影响及由此产生的对胶合性能的影响。研究结果表明,不同染料和染色工艺对刨花表面的相对自由基浓度有显著影响,染色对ＯＳＢ无不良影响     

定向结构刨花板吸声性能的研究

采用驻波管法测定定向结构刨花板的吸声系数,分析比较了定向结构刨花板与砖、混凝土吸声性能的差异。结果表明,定向结构刨花板具有良好的吸声性能。     

Effect of mat structure on modulus of elasticity of oriented strandboard

A model to predict bending stiffness of oriented strandboard (OSB) was tested with pilot plant experimental data. The experimental procedure developed in this study is unique in that it allows the model to be tested for extensive vertical configurations of strand angle distribution. After validation, the model was used to simulate a typical three-layer cross-oriented OSB panel with a vertical density profile and strand angle distribution measured on industrial panels. Analysis of the simulated vertical distribution of modulus of elasticity (MOE) indicated that the layers near the panel surfaces contributed much more to the effective parallel panel MOE than those close to the panel thickness center, with 80% of parallel MOE coming from the top 41% of weight and 32% of thickness. The effectiveness of methods to increase parallel bending stiffness through improving mat structure was evaluated. Increasing face/core weight ratio from 54/46 to 66/34 resulted in a 3.7% increase in simulated parallel MOE. Alignment of strands in face layers was identified having a greater potential to increase parallel MOE. Simulations with three improved strand angle distributions showed gains of 5.7, 12.0 and 19.8% in parallel MOE compared with a typical strand angle distribution of industrial OSB panels.     

竹材是我国制造OSB的一种潜在原料

定向刨花板(OSB)是近20年人造板家族中发展最迅速的一种板材。国外已呈现原料供应不足状况。我国OSB制造业正在起步阶段,将来也会面临原料资源问题。我国是世界第一产竹大国,通过分析竹材的理化性质和采用毛竹进行压板试验,结果表明竹材极有可能替代木材成为制造OSB的一种新原料。