Experimental Study on Withdrawal Performance of Laminated Bamboo Lumber
In order to study the withdrawal performance of laminated bamboo lumber(LBL)under monotonic loading,260 specimens were tested to investigate the effect of the nail type,diameter,ef-fective penetration depth,and angle between the loading and grain of LBL on the failure modes and withdrawal performance.It is found that the failure modes are closely related with the nail type but not nail diameter,effective penetration depth,and loading angle.No visible failures were found in the specimens inserted by the smooth-shanked nail.For screws and twist nails,significant failure phenom-ena were recorded,including bamboo fibers shear failure around the nail,and bamboo fiber in the LBL members were cut off and pulled out of the specimens.The maximum withdrawal resistance in-creases with the increase of the nail diameter and effective penetration depth,and the withdrawal ca-pacity in the longitudinal direction is slightly lower than that in the transverse direction.For the speci-mens with the same nail diameter,the ultimate withdrawal capacity of screws and twist nails in the longitudinal direction is 2.6 times and 1.3 times that of smooth-shanked nails,while the capacity of screws and twist nails in the transverse direction is 2.3 times and 1.2 times that of smooth-shanked nails,respectively.Good agreement between the experimental results and the theoretical results pre-dicted by the suggested formula is achieved,and the error is not greater than 13％.
万方数据
维普
