The effect of a concrete plinth on structure-borne sound power transmission: Theory and numeric simulations

Fenglei Zu, Cheuk Ming Mak

Research output: Journal article publicationJournal articleAcademic researchpeer-review


Concrete plinths are commonly used by engineers as a base for vibratory building services machines. However, it is not clear what effects they have on the structure-borne sound power transmission and the eigenfrequencies of floors. In this paper, the modal functions, eigenfrequencies, and mobility expression of a floor with a concrete plinth attached are deduced. The power transmissibility method is used to analyze the effect of a concrete plinth on the power transmissibility that is used to assess the performance of vibration isolation. It is found that the effect of a concrete plinth is mainly to decrease the eigenfrequencies of the floor, and changing the thickness of the concrete plinth has a greater effect on the eigenfrequencies of the floor and the power transmissibility than does changing the area of the concrete plinth. An estimated equation for power transmissibility is formulated.
Original languageEnglish
Pages (from-to)107-123
Number of pages17
JournalJournal of Low Frequency Noise Vibration and Active Control
Issue number2
Publication statusPublished - 1 Jun 2011


  • Concrete plinth
  • Distributed mass
  • Eigenfrequencies
  • Modal functions
  • Power transmissibility

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Building and Construction
  • Acoustics and Ultrasonics
  • Mechanics of Materials
  • Geophysics
  • Mechanical Engineering

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