- 期刊
用膠量與載重水準對柳杉及杉木定向粒片板之潛變性質影響
Effect of Resin content and Load Level on Creep Behavior of Japanese Cedar and China-Fir OSB
摘要
本報告係探討酚膠用膠量4.5%及6.5%之柳杉及杉木定向粒片板（OSB）在20%及40%載重水準下，彎曲潛變特性，其結果如次：（1）柳杉及杉木OSB在20%及40%載重水準下，其撓度均會隨潛變時間延長而呈曲線狀增大，但柳杉OSB之潛變撓度會大於杉木OSB。（2）在20%載重水準下，瞬間撓度無明顯差異，但40%載重水準下，則柳杉OSB會較杉木OSB大20%~23%。（3）用膠量對OSB之瞬間撓度之影響是於40%載重水準時才會表現出來。但對潛變撓度之影響則不明顯。（4）在40%載重水準下，各試材之潛變撓度均會大於20%載重水準者，柳杉OSB大1.8~2.0倍，杉木OSB大1.5~1.7倍。（5）柳杉及杉木OSB之相對潛變均會隨潛變時間增加而呈曲線或直線狀增大。柳杉OSB之相對潛變不受載重水準之影響，其值介於1.4~1.7之間。杉木OSB之相對潛變係40%載重水準者（1.2~1.45）會明顯的大於20%載重水準者（1.0~1.3）（6）在20%及40%載重水準下，柳杉及杉木OSB在潛變荷重720小時後會顯著降低其MOE殘留率，但MOR殘留率尚可保留70%以上。
並列摘要
This study was to investigate the feasibility to utilize small-diameter trees for making composite panels for structural uses. Oritented strand board (OSE) laboratory- fabricated with flakes prepared from Taiwan-Grown small-diameter Japanese cedar and China -fir were tested in flexural creep in an environmental conditions of 65% RH an 23.9 °C to evaluate the effect of phenoic resin content and load level on the creep performance of these two panel products. The results are summarized as follows: (1) Under load conditions of 20% and 40% MOR, the creep deflection of both group increased nonlinearly as time elapsed. However, the magnitude of creep deflection for Japanese cedar OSB was much greater than that of China-fir group. (2) Under load condition of 20% MOR, significant difference between instantaneous deffections of Japanese cedar China-fir groups was not observed. However, when the load was increased to 40% MOR level, value for Japanese cedar group was 20%~23% higher than that of China-fir group. (3) Effect of resin content on the instantaneous deflection showed markedly when load was at 40% MOR level but such effect on the creep deflection was not significant. (4) 1.8~2.0 times 1.5~1.7 increase of creep deflection, respectively for Japanese cedar OSB and China-fir OSB resulted as the load level increased from 20% to 40% MOR. (5) The relative creep of both OSB groups increased linearly or non-linearly as creep time increased. The values of Japanese cedar groups ranged from 1.41.7 and significant effect of load level was not observed. However, for China-fir OSBs, values of 40% MOR load level group (1.20~1.45) were relatively higher than that of the 20% MOR's (1.0~1.3). (6) Under both load level conditions, significant decrease of MOE was found in both OSB groups after being load in bending for 720 hours. However residual bending strength in both OSB group was less affected and it has about 70% of their original vlaues.