應用細格化幾何探討定向粒片板之抗彎性質

本研究係以柳杉薄片熱壓膠合製成定向粒片板為主要試驗材料，探討其抗彎性質。透過薄片拉伸試驗，取得縱向與橫向之楊氏模數分佈範圍與成板之配向度分佈，藉由蒙地卡羅法與Hankinson 等式，將全域下多層薄片疊加成一模擬單元體，簡化複雜多層之定向粒片板結構，並代入細格化幾何單元於有限元素模擬中計算其抗彎性質。試驗結果指出，縱向之薄片抗拉試驗時，其載重位移圖顯示木材於微小尺度拉伸下呈現一彈塑性材料性質，而此反應與大尺寸試材反應不同；另外蒙地卡羅法與理論式進行轉換後組成之單元體楊氏模數，其縱向拉伸楊氏模數平均值為2.18 GPa；而依據有限元素法模擬與實際值進行比較，結果顯示成板配向度與MOE 之趨勢相同，模擬與實際值之誤差為5 ~ 30 %，其中落差可用更多材料參數條件進行校正，另依據單元局部反應圖檢視之，其應力分佈圖亦可呈現不同配向度下成板之局部反應性質。透過本次研究模型建立與數值分析，可對於定向粒片板之微觀構造加以解析，並於有限元素模擬中有效展現其微觀性質。

關鍵字

定向粒片板；蒙地卡羅法；有限元素法

並列摘要

In this study, we developed the oriented strand board (OSB) as the main test material, and discussed its bending properties. Through the tensile test, the distribution range of the Young's modulus in the longitudinal and transverse directions and the distribution of orientation were obtained. The Monte Carlo method and the Hankinson equation were used to simplify multi-layered structure into an analog element, and replacing the fined geometric element in the finite element simulation to calculate the flexure properties. The results showed that the load displacement diagram exhibited the properties of an elastoplastic material under the small specimen, and the reaction was different from large size specimen. In addition, the average tensile Young’s modulus of element, transferred from Monte-Carlo simulation and theoretical equations was 2.18 GPa, and the simulation results of the finite element method are compared with the actual values. The results showed that the relationship of orientation and modulus of elasticity (MOE) was same with the experiment. The error was about 5 ~ 30%, of which can be corrected with more material parameters. Local stress response could also show difference of orientation by the local stress diagram. Through the establishment of this model and numerical analysis method, we could analyze the microstructure of OSB, and effectively present its microscope properties in finite element simulation.

並列關鍵字

Oriented strand board ； Monte-Carlo method ； Finite element method

參考文獻

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[8] Zhang M, Wong ED, Kawai S, Kwon JH (1998) Manufacture and properties of high-performance oriented strand board composite using thin strands. J Wood Sci 44: 191-197

[9] Suzuki S, Takeda K (2000) Production and properties of Japanese oriented strand board I: Effect of strand length and orientation on strength properties of sugi oriented strand board. J Wood Sci 46: 289-295

[12] EGGER (2014) Frequently asked questions about OSB. Österreich, Fritz Egger GmbH & Co. OG Holzwerkstoffe. pp 1-20

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應用細格化幾何探討定向粒片板之抗彎性質

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