Theoretical Building Height Limits of Balloon Mass Timber Shear Wall Systems

Abstract

Balloon-type mass timber shear walls are one of the most efficient structural systems to resist lateral loads induced by earthquakes or high winds. They are a viable solution for high-rise buildings because they have several key advantages, such as reducing connections and avoiding accumulating compression perpendicular to grain in the floors. This system, however, is not included in current Canadian building code and has no design guidelines in the Canadian timber standard, so it is out of reach of most designers. A multiyear research project has been initiated to quantify the system performance and develop the necessary technical information to codify balloon-type mass timber shear walls. In this paper, the limits for the building height of balloon mass timber shear walls were investigated theoretically. A mechanics-based analytical model was developed to analyze the building height limits governed mainly by the mass timber panels. The influence of loading types (seismic versus wind loads), lateral load levels, panel deformation contribution, seismic force modification factors, and vertical joints between panels on the building heights was investigated using the developed model. The results of this study will give a valuable insight into the seismic performance of balloon type cross-laminated timber (CLT) shear walls.