胶合木自攻螺钉拉拔锚固性能试验研究

Experimental Study on Anchorage Capacity of the Self-tapping Screws in Glulam

进行了不同锚固长度自攻螺钉拉拔强度的试验。研究了自攻螺钉拉拔的破坏形态,不同锚固长度以及自攻螺钉直径对拉拔强度的影响。试验结果表明:绝大多数试件发生木材的剪切破坏和自攻螺钉屈服破坏,个别试件发生劈裂破坏。自攻螺钉连接的拉拔承载力随锚固长度的增加而增大,当锚固长细比达到16时,试件发生自攻螺钉屈服破坏,属延性破坏;弦向锚固试件极限拉拔荷载均大于径向锚固试件。

A pull-out experiment of self-tapping screws in glulam was conducted. The failure modes were discussed and the influence of different anchorage distances and different screw diameters were compared. The majority of specimens failed in the shear mode of wood and the yielding failure of screws, while the splitting failure occurred in only one specimen. The pull out load of self-tapping screws increased with the increasing of anchorage length. The ductile failure of yielding screws occurred with the slenderness ratio of screws up to 16. In addition, the ultimate pull out load of tangential specimens were larger than that of the radial anchored ones.