Flanking sound transmission over CLT-joints

Abstract

Cross-laminated timber (CLT) is a sustainable and efficient building material that has gained popularity due to its high stiffness, low density, and reduced environmental impact. However, predicting low-frequency sound and vibration transmission across CLT joints remains a significant challenge. This thesis focuses on improving the modeling of flanking sound transmission over different CLT joint configurations, using finite element modeling (FEM) validated through experimental measurements. The study involves measurements of vibration reduction index (Kij) for undamped and isolated joint setups. The FEM simulations closely matched experimental trends for non isolated setups, though some discrepancies arose due to possible differences in coupling conditions and measurement resolution. In isolated setups, FEM predictions highlighted limitations in accurately simulating the effect of vibration-isolation brackets, particularly in representing their behavior when fastened to the CLT panels. The results emphasize the need for refined FEM approaches to better model the dynamic behavior of joints and connections in CLT structures. Future work should focus on enhancing joint coupling simulations, modeling of vibration-isolation brackets and optimizing experimental setups to achieve free boundary conditions. Thereby advancing the acoustic performance prediction for CLT constructions.