原竹增强空心刨花板材性分析及其轴向抗压稳定性设计

摘要

Small-diameter-original bamboo was used to improve some properties of extrude particleboards (EP).Meanwhile,using LVL and plywood as surface materials to further modify original bamboo reinforced particleboards,which could provide the perspectiveness for new materials development.The properties were determined by physical and mechanical properties.According to the Eurler's formula,the reference values of stability design for longitudinal compression were obtained.The results showed that mechanical properties and dimensional stability of EP were greatly improved by bamboo addition.Bamboo cortex had certain influence on IB of the composite.The dimensional stability of EP could be improved by using original bamboo and facing materials.The influence of different facing materials on TS was not significant,but with great influence on LDC.The bending property of LBRP was better than that of PBRP.MOR and MOE value of BRP materials modified with LVL were 37.84 MPa and 14 577 MPa,respectively.It also showed that these values were influenced by different facing materials,especially for the effect on MOE.Additionally,the value range of safety design for longitudinal compression was obtained by theoretical design and calculation.%以小径级原竹为增强材料,改善空心刨花板(EP)主要物理力学性能.同时,通过LVL和胶合板,对原竹增强刨花板进行覆面改性,为新材料的开发利用提供参考.通过对复合材料物理、力学指标进行测试,评定材料性能.并基于欧拉公式,对其作为轴向抗压材料进行稳定性设计.结果表明:原竹结构对EP材性有显著性影响,力学性能和尺寸稳定性均显著提高.其中,竹青对复合材料的内结合强度(IB)具有一定影响;原竹和覆面材料的加入可综合改善EP尺寸稳定性.不同覆面材料对吸水厚度膨胀率(TS)影响不显著,但对长度方向尺寸变化(LDC)影响显著;LVL改性材(LBRP)抗弯性能优于胶合板改性材(PBRP).其中LBRP材料静曲强度(MOR)达到37.84 MPa,弹性模量(MOE)达14 577 MPa;不同覆面材料对MOR和MOE均有显著影响,但对MOE影响更为显著.此外,通过理论设计和计算,得到了轴向抗压材料的安全设计参考值范围.