Investigating the effect of perpendicular walls on the lateral behaviour of Cross-Laminated Timber shear walls

Cross-Laminated Timber (CLT) structures are realized by joining CLT panels using metal connections, which represent the main source of deformability for lateral loads and energy dissipation in case of seismic events. CLT building construction types can be distinguished in “box type”, in which the perpendicular walls in the corner of the building are joined along the wall vertical edges, and “shear wall type”, in which the perpendicular walls in the corner of the building are not mutually connected. Regardless of the construction type considered, the calculation models used to design the shear walls of CLT buildings take into account the connections at the base of the shear walls, while neglecting the presence of connections between perpendicular walls. This paper presents a study on the effects of the perpendicular walls on the lateral response of CLT shear walls. Two analytical models of laterally loaded CLT shear wall that consider the wall base connections, hold-downs and angle brackets, and the contribution of the connections between the shear wall and the perpendicular wall are presented. These analytical models were validated against two- and three-dimensional numerical models developed in SAP2000. Both analytical and numerical models are used to perform a parametric analysis in which different geometrical and mechanical properties of CLT shear walls are considered. The aim of the parametric analysis is to validate the correctness of the analytical models and to quantify the increase of lateral stiffness and lateral capacity of the shear wall due to the interaction with the perpendicular wall. Results showed that the interaction between shear wall and perpendicular wall increases the rocking stiffness, the lateral capacity, and modifies the rocking behaviour of the shear wall.