Effect of the Structural Interactions in Multi-Story CLT Shear Walls

A CLT platform building is made up of horizontal and vertical panels, which are assembled on site to obtain a "box-type" structure, in which the lateral load resisting system consists of the assembly of different shear walls with their base connections, and other typologies of connections. The lateral behavior of a CLT platform building is governed by the wall base connections, but also influenced by different structural interactions including those between floor and wall segments and those between lintels and wall segments. The magnitude of the interactions between lintels and wall segments depends on the construction technique chosen for creating the openings, which can be realized through monolithic or assembled shear walls. Although multi-story CLT shear walls realized with these two different construction techniques exhibit a different lateral behavior, often, the same simplified modelling strategy is considered in the design practice, neglecting relevant aspects of the lateral behavior such as the structural interactions. This paper investigates in detail the differences of the lateral behavior of multi-story CLT shear walls realized with these two construction techniques by considering both simplified modelling strategies and more advanced modelling strategies, which consider the structural interactions between floor diaphragms and wall segments and between lintels and wall segments. Results of nonlinear static analyses showed significant differences between the two modelling strategies in terms of lateral performance and failure modes of the systems, emphasizing that simplified modelling strategies cannot always be reliable methodologies to describe the behavior of multi-story CLT shear walls.