Vibration Performance of Mass Timber Slab Floors with Glulam Beam Supports

Abstract

Mass timber floors are prone to human-induced vibration due to their light weight. Vibration serviceability limit design often governs the maximum allowable span of mass timber floors. The current design methods usually assume the mass timber floors are simply supported on walls, which cannot be directly applied to floors being supported by beams. In this study, the vibration performance of mass timber floors including nail laminated timber, dowel laminated timber, and cross laminated timber floor panels with beam supports was investigated experimentally. Various equations for predicting the system’s fundamental natural frequencies were assessed based on the experimental results. Additionally, a finite element model was proposed and validated using the test results for further vibration analysis. The test results highlighted the substantial influence of support stiffness on the dynamic properties and vibration performance of the floor systems. Specifically, when changing from wall supports to beam supports, the floor’s fundamental natural frequency decreased by up to 40%. This change in support resulted in a shift in vibration performance ratings from acceptable to unacceptable. Dunkerley’s equation and the equation in the draft version of the second generation of Eurocode 5 consistently produced overestimated results for up to 30% when predicting the system’s fundamental natural frequency. In contrast, Kollar’s equation displayed an average error within 5%, with the modification introduced in this research, it demonstrated promising potential for practical application.