Tension resistance properties of hold-down and angle-bracket connections on cross-laminated timber (CLT)

Abstract

The goal of this study was to propose a practical approach for predicting the tension resistance properties of hold-down (HD) and angle-bracket (AB) connections on cross-laminated timber (CLT) by using modified design equations. The effects of wood density and number of screws on the tension properties of screwed HD and AB connections were experimentally investigated. Pine CLT connections with lower wood density exhibited lower tension resistance (−39%) and yield displacement (−34%) but higher ductility ratio (91%) relative to those of larch CLT connections. The AB connections on larch CLT exhibited lower elastic stiffness (−25 to −53%) and tension resistance (−10 to −22%) than those of the HD connections. The different load distributions of the HD and AB connections led to different failure behaviors associated with wood species. Although the tension resistance of the CLT connections was directly proportional to the actual number of screws, the elastic tension stiffness of the CLT connections was not directly proportional to the actual number of screws. Based on these experimental results, group effects on the tensile properties of the HD and AB connections on CLT were accounted for in the design equations, and the difference between the elastic stiffness, tension resistance, and ductility ratio values predicted using the developed design equations and the corresponding experimentally obtained values were 8, 6, and 7%, respectively.