Seismic Performance of Prefabricated Modular Mass Timber Structures with Inter-Story Isolation.

Abstract

Prefabricated Modular Mass Timber (MMT) construction provides an alternative to traditional on-site light timber construction. MMT buildings comprise of prefabricated volumetric modules assembled on-site to form a larger, permanent building. Because the prefabricated modules are constructed off-site in a controlled environment, they offer consistent quality, resource efficiency, and a sustainable building solution. However, numerous research and experimental test have shown that conventional connections used to facilitate the assembly of prefabricated modules in MMT construction do not meet the damage avoidance and sustainability criteria of mass timber design. This paper proposes an innovative Resilient Floor Isolation System (RFIS) for MMT construction. The proposed systems effectiveness and advantages have been investigated and illustrated in this paper. Numerical modelling of MMT with story isolation at intermediate levels was developed in ETABS. The seismic performance of MMT with inter-story isolation was evaluated using static pushover and non-linear dynamic time history analysis and compared with a conventional mass timber building without inter-story isolation. Data from time history analysis revealed that introducing inter-story isolation at intermediate levels of a building reduces the force demands on prefabricated MMT, thus leading to an improved seismic response. The findings of this research exemplify that the proposed concept can be a potential candidate for low-rise mass timber buildings made of prefabricated MMT.

KEYWORDS: Mass timber, Prefabricated modules, Inter-story isolation, Low damage, Non-linear dynamic time history analysis, Numerical model