Reverse-cyclic performance of United States prescriptive code connectors in a novel mass timber structural composite panel

• Published in: Case Studies in Construction Materials Vol. 21; p. e03524
• Main Authors: Morrell, Ian, Sinha, Arijit, Cheney, Daniel, Taylor, Robert, Potter, Frank, Way, Daniel, Deboodt, Tyler
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2024
• Subjects: Connections; Mass timber; Structural composite lumber; Connections; Mass timber; Structural composite lumber
• ISSN: 2214-5095; 2214-5095
• DOI: 10.1016/j.cscm.2024.e03524

Mass timber has been recently increasing in popularity, especially panel products such as cross-laminated timber (CLT), which has spurred innovation in creating new mass timber materials. One recent mass timber material utilizes structural composite lumber to create a PRG-320 compliant CLT, referred to as a structural composite panel (SCP). To increase the knowledge on the connection performance of the new SCP, reverse-cyclic testing was conducted on standard mass timber panel prescriptive connection systems within U.S. codes with SCP as the substrate. Three different types of tests were conducted: shear tests of a floor-to-wall connector, uplift tests of the same floor-to-wall connector, and shear tests of an inter-panel connector. Two monotonic and six reverse-cyclic tests were done per test configuration. The connections typically failed through a combination of wood failure and either nail bending and withdrawal or nail fracture. Two cyclic tests of the floor-to-wall connector in shear and all tests of the floor-to-wall connector in uplift failed through fracture of the plate connection. Results were compared to previous testing on CLT that was used to validate the connection and design methodology. Higher maximum strengths were observed when comparing the SCP to previously tested CLT, with an average increase of 20 percent. The displacement at maximum force and ultimate displacement capacity were similar between the SCP and previous CLT connections. Connections in SCP exhibited a lower stiffness than comparable CLT specimens for all tests, with an average difference in stiffness of 33 percent. This led to a comparatively lower ductility for the SCP specimens than for the CLT. ASCE 41 trilinear parameters were derived for all cyclic tests to aid in the utilization of the connections with this new material. •Characterized reverse-cyclic performance of connections in new mass timber material.•Material exhibited higher strengths than previous tests in CLT with same connection.•Stiffness was lower in new material compared to CLT with same connection.