Abstract Summary
Cross-laminated timber (CLT) is a wood-based multilayer composite made of several thin layers glued together in a crosswise manner. Modern manufacturing techniques resulted in CLT panels with remarkable stiffness properties and unique aesthetic appeal. CLT panels are commonly produced in a rectangular shape, while CLT floors are typically an assembly of prefabricated panels connected together on the site. Floors are usually simply supported on two opposite edges (SFSF) or all four edges (SSSS). Still, architectural design often requires non-conventional, complex-shaped floors with openings and boundary conditions that differ from those mentioned above. High stiffness-to-mass ratio of the CLT panels enabled structural engineers to design long-span CLT floors. However, they are prone to vibrations induced by active people; thus, vibration serviceability assessment often governs their design. There are different design guidelines for the design of CLT floors. Proposed design methods range from traditional, formulated to limit the fundamental frequency and/or static deflection, to modern performance-based assessment approaches. All these guidelines are limited to SFSF and SSSS rectangular floors. Furthermore, neither of them takes into account the inter-panel connections in vibration serviceability assessment. Bearing all this in mind, available CLT design guidelines do not apply to non-conventional CLT floors. On the other hand, Arup's design guideline for footfall-induced vibrations offers a universal assessment framework that applies to any floor structure regardless of its geometry, material, and boundary conditions. It has gained a good reputation globally for being robust and reliable in designing concrete and composite floors. This paper presents a numerical vibration analysis of a complex-shaped CLT floor with openings that can be used as a standard floor structure of residential-commercial buildings. Based on its size and shape, the floor is assembled using five CLT panels. It was found that the panel orientation, inter-panel connections, and their position in the floor outline significantly affect the floor modal properties. Numerical simulations of vibration response induced by single pedestrian walking showed that some floor configurations are better than others from the vibration serviceability assessment point of view.
