Effect of Member Thickness and Nail Length Projecting from Main Member on Shear Performance of Single Shear Nailed Joints

Single shear tests were conducted on nailed timber joints with varying main member thickness, side member thickness and nail length projecting from the main member, and their effects on various shear performances of nailed joints were investigated. Initial stiffness and yield load of nailed joints were almost constant when the ratio of main member thickness to nail diameter (lm/d) was 7-14 and 10-14, respectively. Maximum load and energy capacity increased as main member thickness was greater and showed the highest values when lm/d was 13-17 and 13-15, respectively. Maximum load of nailed joints with lm/d of 9 was 36% lower than that of nailed joints with lm/d of 13-17. Energy capacity of nailed joints with lm/d of 9 was 58% lower than that of nailed joints with lm/d of 13-15. Regardless of nail length projecting from the main member (lnp), initial stiffness of nailed joints with lnp was close to that of nailed joints without lnp. When the ratio of the sum of lm and lnp to nail diameter ratio (lr/d) was 10-11, maximum load and energy capacity of nailed joints with lnp were close to those of nailed joints without lnp. When lr/d was 12-15, maximum load and energy capacity of nailed joints with lnp were lower than those of nailed joints without lnp. When nailed joints have a member thickness according to the standard for structural design of timber structures edited by Architectural Institute of Japan, initial stiffness and yield load are little affected by member thickness but maximum load and energy capacity are greatly affected by member thickness.