On the low frequency impact noise of massive floors – a case study

Abstract

The issue of impact noise sound pressure level respectively the impact noise sound insulation is frequently discussed topic in relation to the lightweight floors, elastic, or plastic impact excitation, locally or resonantly reactive floors in relation to the rigid heavy weight basic floors etc. In practice one can face the situation, when the standardized requirements on flooring system are fulfilled, but neighbors are still disturbed by low frequency impact noise generate by walking even on heavy floors. To understand the reasons, sometimes only measurements by microphones based on sound pressure level determination may not be sufficient enough. The interaction of the excitation device (tapping machine or so) and ceiling systems has already been demonstrated and also several effective numerical approaches how to predict the damping ability of the ceiling system against impact excitation. A good knowledge of the individual parts of the construction structure as well as the characteristics and properties of the excitation source is essential in each new flooring system design or development process. As part of the national grant VEGA 1/0205/22 focusing on low-frequency impact noise the precise analysis of basic massive testing floor and its reaction on the tapping machine and standardized rubber ball excitation was investigated. The conventional measurement technique based on microphone measurement as well as vibration measurement based analysis were compared. The analysis was supported by numerical model.