Effect of Loading Speed on the Mechanical Properties of Nail Joints

Wood shear walls are the main lateral load resisting systems in light wood frame buildings to resist the wind and seismic loads. Sheathing to lumber nail connections are regarded as the key components that control the resistance and failure modes of wood shear walls. Considerable experimental tests have been conducted on performance of nail joints or wood shear walls under both static and reversed cyclic loads. However, these tests were usually conducted under different loading speed causing specimen failure in 1 min to an hour. It is unclear how the loading speed will affect the test results of nail joints or wood shear walls. Research on these topics is limited. This paper aims to evaluate the effect of loading speed on the mechanical characteristics of nail joints. 72 specimens have been tested under various loading speeds, ranging from 0.05 mm/s to 0.5 mm/s for monotonic tests and 1.5 mm/s to 15 mm/s for reversed cyclic tests. The range of loading speed was selected based on the total estimated loading time that both monotonic and reversed cyclic tests fail within around 1 min to 10 min. Two groups of nail joints, comprising two common nail sizes and two sheathing thicknesses, were assessed under both monotonic and reversed cyclic loads. From the test results, the effect of loading speed on the mechanical properties of nail joints was determined.