Vibration reduction of thermal break balcony connections

Abstract

In energy efficient buildings concrete balconies have to be thermally insulated from the concrete floor to reduce heat loss and to increase surface temperature. This thermal break is obtained by polystyrene in combination with high-strength concrete thrust-force bearings and an arrangement of stainless steel straight and bent bars to act as tension and shear reinforcement. The acoustic performance of such thermal break units was investigated under laboratory conditions. Therefore the vibration level difference at different junctions between balcony and the thermal isolated concrete floor as well as the normalized impact sound pressure level of the floor when the balcony is excited with the standard tapping machine are measured. The influence of the number of tension and shear steel bars and the type of thermal insulating material was studied on typical sized balconies connected to small test floors. The vibration isolation at low frequencies was determined using modal testing.