Influence of perpendicular wall interactions on the lateral behaviour of multi-storey cross-laminated timber structures: An analytical and numerical study

This study examines the structural interactions between shear walls and perpendicular walls in multi-storey Cross-Laminated Timber (CLT) buildings, focusing on their effects on lateral stiffness, load-bearing capacity, and force distribution. The study, carried out through a combination of analytical modelling, numerical simulations, and parametric analyses, indicates that perpendicular walls can increase the lateral stiffness of CLT systems by up to 100 %, depending on the stiffness of the hold-down and the wall-to-wall connections. The study introduces force-sharing coefficients, showing that perpendicular walls increasingly absorb overturning forces as the stiffness of their hold-down and the wall-to-wall connections increases. Consequently, this mechanism reduces the lateral load on shear walls by up to 50 % allowing for a more effective distribution of lateral forces. Furthermore, perpendicular walls contribute to reduced lateral displacements, with numerical results revealing reductions of up to 20 % in the top storeys. These outcomes emphasize the stabilizing role of perpendicular walls in multi-storey CLT configurations, contributing to controlled lateral displacements and improved structural stability under lateral loading conditions. The results also suggest that optimizing perpendicular wall connections could further increase the resistance to lateral loads, which is particularly valuable for seismic design applications. This study underscores the importance of integrating perpendicular wall interactions in CLT design practices to enhance the performances of timber buildings supporting future developments in analytical modelling and performance-based design for CLT systems.