結構用自攻螺絲在木材之垂直引拔抵抗性能評估

Evaluation of the Performance of the Vertical Withdrawal Resistance of Structural Self-tapping Screws in Wood

葉民權(Min-Chyuan Yeh) ； 林玉麗(Yu-Li Lin) ； 宋雲煒(Yun-Wei Sung)

《台灣林業科學》 33卷2期 (2018/06) Pp. 109-123

https://doi.org/10.7075/TJFS.201806_33(2).0003

摘要

本研究採用直徑6~12 mm、長度200~302 mm之5種結構用自攻螺絲，探討對柳杉、花旗松、南方松、冰片木四種樹種木材之垂直引拔抵抗之影響。根據自攻螺絲穿透試驗結果顯示，結構用自攻螺絲在冰片木之單位長度垂直引拔強度高於柳杉65.3%，花旗松與南方松兩者條件結果相近且高於柳杉材49.6%。直徑10與12 mm之結構用自攻螺絲在木材的單位長度垂直引拔強度平均高於6 mm直徑條件50.0%，也高於8 mm直徑33.3%。根據螺紋長度全部鎖入木材之試驗結果顯示，單支結構用自攻螺絲在冰片木的垂直引拔容量高於柳杉材28.8%，而花旗松及南方松兩者條件之結果則與柳杉相近。直徑 12 mm之單支結構用自攻螺絲在木材的垂直引拔容量為直徑6 mm條件者2.42倍，直徑10 mm結構用自攻螺絲亦為直徑6 mm條件者2倍。在8 mm直徑之結構用自攻螺絲其釘尖具木材切削刃者在木材之垂直引拔容量高於釘尖具金屬切削刃者32.1%。結構用自攻螺絲在木材的垂直引拔抵抗性能主要是受到木材密度、自攻螺絲直徑、有效螺紋長度以及釘尖型式之影響。

關鍵字

自攻螺絲 ； 集成材 ； 垂直引拔抵抗 ； 柳杉 ； 冰片木

並列摘要

Five structural self-tapping screws with a diameter of 6~12 mm and a length of 200~302 mm were used to investigate the withdrawal resistance performance in wood species of Japanese cedar, Douglas fir, southern pine, and Kapur. Based on results of the penetration-through tests, the withdrawal unit force of a structural self-tapping screw for Kapur was 65.3% higher than that of Japanese cedar. Douglas fir and southern pine showed similar withdrawal resistance values and were 49.6% higher than that of Japanese cedar. The average withdrawal unit force obtained using 10- and 12-mm structural self-tapping screws was 50.0 and 33.3% higher than that using 6- and 8-mm self-tapping screws, respectively. Based on the test results of the screw length fully embedded in wood, the withdrawal capacity of a single structural self-tapping screw in Kapur was 28.8% higher than that in Japanese cedar. The results obtained from both Douglas fir and southern pine were close to that of Japanese cedar. The withdrawal capacities of single12- and 10-mm structural self-tapping screws were 2.42-and 2-times, respectively, that of 6-mm screws. The withdrawal capacity of single 8-mm structural self-tapping screws with a wood-drilling tip was 32.1% higher than that of screws with a metal-drilling tip. The withdrawal resistance performance of the structural self-tapping screws in wood was mainly influenced by the wood density, screw diameter, effective screw length, And type of screw tip.

並列關鍵字

self-tapping screw ； glulam ； withdrawal resistance ； Japanese cedar ； Kapur