Development of Modular System in Midrise to Tall Wood Buildings Phase II

https://research.thinkwood.com/en/permalink/catalogue2530
Year of Publication
2020
Topic
Design and Systems
Material
CLT (Cross-Laminated Timber)
Author
Zhang, Chao
Organization
Timber Engineering and Applied Mechanics (TEAM) Laboratory
Year of Publication
2020
Country of Publication
Canada
Format
Report
Material
CLT (Cross-Laminated Timber)
Topic
Design and Systems
Keywords
Openings
Lateral Performance
Shear Walls
SPF
Spruce-Pine-Fir
Loading Tests
Language
English
Research Status
Complete
Summary
This project studied the effect of openings on the lateral performance of CLT shear walls and the system behavior of the walls in a module. Three-layer Cross Laminated Timber (CLT) was used for manufacturing the wall and module specimens. The laminar was Spruce-Pine-Fir (SPF) #2&Better for both the major and minor layers. Each layer was 35 mm thick. The panel size was 2.44 m × 2.44 m. Four configurations of walls were investigated: no opening, 25% opening, 37.5% opening, and 50% opening. The opening was at the center of the wall and in the shape of a square. A CLT module was made from two walls with 50% openings, with an overall thickness of 660 mm. The specimens were tested under monotonic loading and reverse-cyclic loading, in accordance with ASTM E564-06 (2018) and ASTM E2126-19. The wall without opening had an average peak load of 111.8 kN. It had little internal deformation and the failure occurred at the connections. With a 25% opening, deformation within the wall was observed but the failure remained at the connections. It had the same peak load as the full wall. When the opening was increased to 37.5%, the peak load decreased by 6% to 104.9 kN and the specimens failed in wood at the corners of the opening. Further increasing the opening to 50%, the peak load dropped drastically to 63.4 kN, only 57% of the full wall. The load-displacement relationship was approximately linear until the load reached 60% of the peak or more. Compared to the full wall, the wall with 25% opening had 65% of the stiffness. When the opening increased to 37.5% and 50%, the stiffness reduced to 50% and 24% of the full wall, respectively. The relationship between stiffness and opening ratio was approximately linear. The loading protocol had effect on the peak load but not on the stiffness. There was more degradation for larger openings under reverse-cyclic loading. The performance of the module indicated the presence of system effect that improves the ductility of the wall, which is important for the seismic performance of the proposed midrise to tall wood buildings. The test data was compared to previous models found in literature. Simplified analytical models were also developed to estimate the lateral stiffness and strength of CLT wall with openings.
Online Access
Free
Resource Link
Less detail