Experimental and Reliability-Based Investigation on Sheathing-to-Framing Joints under Monotonic and Cyclic Loads

Abstract

The seismic performance of a light wood frame structure is determined by sheathing-to-framing joints. In order to encourage the use of more sustainable materials in structures, the spruce-pine-fir (SPF) panel and the bamboo scrimber (BS) panel were considered as sheathing materials. Monotonic and cyclic tests were conducted on the joints with different parameters to obtain their mechanical properties. Moreover, the design value of the bearing capacity of sheathing-to-framing joints was calculated and compared in accordance with Chinese code (GB50005) and European code (Eurocode 5). Based on the test results and the design codes, the reliability index of the design value of the bearing capacity of joints was calculated using the first-order reliability method (FORM). Results demonstrate that the joints have high bearing capacity and stiffness at initial loading stage when the loading direction is perpendicular to the framing grain. BS panels make better use of the bending strength of fasteners than SPF panels. The screwed joints have lower strength and stiffness degradation than nailed joints, but the nailed joints show better ductile and dissipation than screwed joints. In addition, the reliability indexes of design bearing capacity calculated by the Chinese code of joints under monotonic load are conservative, but those of joints under cyclic load are unconservative. Therefore, in order to ensure the safety and economy of design, a modification factor for the GB50005 design method of joints is proposed to meet the target reliability index.

Uplift capacity evaluation of light-framed wood structure’s roof-to-wall connections

“…The SPF is a generic term for a class of coniferous specimen lumber, mainly from the United States of America and Canada, including spruce, pine, and fir (Zhang and Cai 2008;Gong et al 2014;Zheng et al 2015;Wang et al 2017;Zhang et al 2021). It is a type of commercial softwood tree species combination wood, with white and clean material appearance, close and meticulous texture, small scar appearance, high strength to weight ratio, and strong nail holding capability (Di and Zuo 2021;Xiao et al 2021). Moreover, SPF is widely used in the construction industry, and could be used in important structural components such as beams and columns (Xiao et al 2017;Wang et al 2019b;Dong et al 2021).…”