Lateral load resistance of light wood frame buildings (LWFB) is generally provided by wood-based shear walls. From an architectural perspective, the requirement for shear walls may lead to problems with respective to space usage in a building and limit building plans with open concept. This issue is compounded when the storey height limit is raised. There is a need to provide alternative bracing systems that will provide the required lateral resistance but still allow for open space in buildings. Portal frame systems have been identified by builders as a viable option to meet this need. However, their application so far has been limited to residential structures up to two storeys high. The main objective of this paper is to investigate the feasibility of using wood or steel portal frame as a substitute for wood shear walls in multi-storey LWFB. Three to six storey tall buildings were analyzed using layouts that represent situations associated with decisions on utilizing efficient space usage. The reference case was the building having wood-based shear walls as the main lateral load resisting system. In the other cases a hybrid approach was utilized for the lateral load resisting systems, and where some of the shear walls are replaced by wood or steel portal frames. The buildings were subjected to various earthquake ground motion excitations, and each ground motion was scaled until excessive inter-storey drift was reached. Structural performance comparison amongst these cases included: drifts, failure behaviour, and force distribution along and between the shear wall lines.
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