Dynamic stiffness measurement of resilient materials

Abstract

Resilient materials are used to achieve vibration isolation in buildings and thus to reduce the transmission of impact sound. To characterise resilient materials, several measurement procedures exist for the determination of the dynamic stiffness of these materials. In the field of building physics, the most commonly used method is described in EN 29052-1. This publication focuses on the dynamic stiffness determination of resilient materials using different methods of excitation of the sample under test. Hammer and shaker excitation were used. It is shown that the method of excitation causes a strong deviation of the measured dynamic stiffness. Tests were performed on two different porous materials. A linear and exponential data extrapolation results were compared and a modification of the measurement set-up by means of a massive frame around the specimen was applied. Additionally the influence of the different methods of excitation on the measured loss factor was investigated as well.