Skip to main content
U.S. flag

An official website of the United States government

Determination of seismic performance factors for cross-laminated timber shear walls based on FEMA P695 methodology

Informally Refereed
Authors: John van de Lindt, M. Omar Amini, Douglas Rammer, Philip Line, Shiling Pei, Marjan Popovski
Year: 2022
Type: General Technical Report (GTR)
Station: Forest Products Laboratory
Source: FS GTR

Abstract

Cross-laminated timber (CLT) construction has been gaining popularity in North America. However, CLT-based seismic force resisting systems are not recognized in current U.S. design codes, which is among the many challenges preventing widespread adoption of CLT in the United States. The purpose of this study was to investigate the seismic behavior of CLT-based shear wall systems and to determine seismic performance factors, namely, the response modification factor (R factor), the system overstrength factor(Ω), and the deflection amplification factor (Cd), using the FEMA P695 procedure. Nine index buildings including single-family dwellings, multifamily dwellings, and commercial (including mixed use) midrise buildings were developed, from which 72 archetypes were extracted. Testing performed at the component and subassembly levels included connector tests and isolated shear wall tests. A CLT shear wall design method was developed and used to design the archetypes, which were then assessed with nonlinear pushover analysis and incremental dynamic analysis. Based on the required collapse margin, an R factor of 3 is proposed for CLT shear wall systems with 2:1 or mixed aspect ratio panels up to 4:1, and an R factor of 4 is proposed for CLT shear wall systems made up of only 4:1 aspect ratio panels. Results from this study have been proposed for recognition in U.S. building codes (such as the International Building Code) through specific change proposals to update reference standards such as ASCE 7 Minimum Design Loads and Associated Criteria for Buildings and Other Structures and Special Design Provisions for Wind and Seismic.

Keywords

cross-laminated timber, seismic design, mass timber design, FEMA P695

Citation

van de Lindt, John; Amini, M. Omar; Rammer, Doug; Line, Philip; Pei, Shiling; Popovski, Marjan. 2022. Determination of seismic performance factors for cross-laminated timber shear walls based on FEMA P695 methodology. General Technical Report FPL-GTR-281. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 515 p.
https://www.fs.usda.gov/research/treesearch/64383