Mitigating footfall-induced vibrations in cross-laminated timber floor-panels by using beech or birch

Abstract

Long-span floors are particularly sensitive to footfall-induced vibrations, making their analysis and design critical for ensuring occupant comfort. Cross-laminated timber (CLT) panels have high stiffness relative to their self-weight and are commonly made of spruce. Hardwoods such as birch and beech possess higher stiffness and mass density, which can potentially improve the vibrational performance of CLT panels. In this study, the vibrational performance of CLT panels made of beech and birch with different mechanical properties was investigated using finite element (FE) models calibrated via experimental modal analysis (EMA) tests, yielding calibration with less than 1% error in natural frequencies. The study demonstrated that birch or beech laminations, compared with spruce ones, can provide a significant mitigation of vibrational responses, both for broadband (to approximately 40% of the spruce reference level) and footfall-induced vibrations (to approximately 20%–30% of the spruce reference level). It is noteworthy that low quality beech can result in a marked amplification that may nearly double the level of footfall-induced vibrations.