Lateral Performance of Nail Connections from Century-Old Timber Floor Diaphragms

AbstractNail connections salvaged from the timber floor diaphragms of two ∼100  year old unreinforced masonry buildings were pseudostatically tested to determine their hysteretic behavior. The research objective was to establish expected load-slip characteristics of nail connections in historic timber diaphragms to facilitate improved seismic assessment accuracy. A summary of the testing procedure, test results, and performance characterization is presented. Nail connections constructed from Kauri (Agathis australis) timber and wire-drawn nails in the 1890s were found to have an average yield strength of 1.0 kN and an average maximum strength 1.4 kN. Nail connections constructed in 1914 from Rimu (Dacrydium cupressinum) timber and wire-drawn nails were found to have an average yield strength of 0.8 kN and an average maximum strength of 1.0 kN. Both connection types exhibited an average ultimate displacement capacity of approximately 11.4 mm.