3rd Croatian Conference on Earthquake Engineering 3CroCEE

Timber construction is increasingly regarded as a key solution for sustainable building due to its low carbon footprint, renewability, and efficiency in prefabrication. These properties, combined with timber’s lightweight and design and construction in combination with steel connectors, make it particularly attractive in seismic regions, where reducing building mass and ensuring energy dissipation are crucial for seismic resilience. Prefabricated timber systems offer both economic and practical advantages, further enhancing their appeal in areas prone to earthquakes.

In this study, a simplified pushover analysis method for timber buildings made of light frame timber panels is presented, intended for practical application by structural engineers. As part of previous research conducted at the Slovenian National Building and Civil Engineering Institute (ZAG) in collaboration with an industrial partner, extensive experimental investigations were carried out on the seismic behavior of light frame timber panels. These panels, consisting of cement-particle boards attached to timber frames with metal staples, were subjected to cyclic shear tests on full-scale specimens. It was observed that panels with cement-particle boards exhibit, as opposed to panels with gypsum-fibre boards, ductile behavior.

The primary objective of this study was to evaluate the behavior factor (q-factor) for a building under seismic loading, providing the manufacturer with confirmation of the performance of their systems and the assumptions made in the design process. This study also aimed to address a gap in existing research and design standards, where behavior factors for timber frame buildings with stapled sheathing are not explicitly defined, posing a challenge in current design practice. The experimental tests conducted in previous research, combined with the findings from this analysis, provide valuable data for refining current seismic design codes, particularly Eurocode 8 (EC8).

A pushover analysis was performed on an existing building, with a critical-story failure mechanism assumed. The methodology of the pushover analysis, based on the SREMB method, is described, with emphasis on the assumptions regarding the nonlinear behavior of the timber panels and their implications for seismic performance based on the case study results. The results and various design assumptions are discussed, focusing on the simplifications made and their appropriateness for practical engineering applications. The broader impact of these findings on the design of timber buildings is also highlighted, along with the need for further research and experimental validation to support the adoption of these methods for design in engineering practice.