Structure-Borne Sound: Structural Vibrations and Sound Radiation at Audio Frequencies
About this book
The propagation of vibration through solid structures and its subsequent radiation as audible sound constitutes a pervasive and often underestimated source of noise in buildings, vehicles, and machinery. Unlike airborne noise, which travels through air and can be attenuated by barriers and absorptive treatments, structure-borne sound is carried by elastic waves in the fabric of constructions themselves, making its control fundamentally a problem of mechanical engineering and structural dynamics. The monograph by Cremer, Heckl, and Petersson, now in its substantially revised third edition published by Springer in 2005, remains the most comprehensive and authoritative treatment of this subject available in the technical literature.
At over 600 pages, it is both a foundational textbook and a working reference for acousticians, structural engineers, and noise control specialists. The book opens with an introductory chapter that orients the reader within the broader landscape of acoustics and sets out the scope and organization of the work. The intellectual genealogy of the volume is significant: its origins lie in the research tradition of Lothar Cremer and Manfred Heckl at the Institute for Technical Acoustics of the Technical University of Berlin, where Cremer served as director from 1954 and Heckl later succeeded him.
The third edition was revised and extended by Björn Petersson, also of TU Berlin, who brought updated formulations and new material to what had already become a standard reference in the field. A central and recurring theme throughout the book is the survey of wave types and their fundamental characteristics in structural elements. Longitudinal waves, in which particles oscillate along the direction of propagation, carry energy efficiently over long distances but radiate sound poorly.
Bending waves, sometimes called flexural waves, involve transverse particle motion and are the dominant mechanism of sound radiation from plates and panels because their wavelengths can become comparable to those of sound in air near the critical frequency — the condition at which radiation efficiency rises sharply. Shear waves and torsional waves in beams and rods are analyzed for their role in specific structural configurations. For each wave type, the book derives dispersion relations, phase and group velocities, and the conditions for free and forced wave propagation in finite and infinite structural systems.
Damping is treated with unusual thoroughness. The chapter on this topic distinguishes between the mechanisms of material damping — hysteretic, viscous, and viscoelastic — and structural damping arising from joints, connections, and boundary conditions. The loss factor, which characterizes the fraction of vibrational energy dissipated per cycle, is introduced and applied across different frequency regimes and material types.
The influence of temperature on viscoelastic materials and the practical techniques for measuring damping in real structures are addressed, providing guidance directly applicable to noise control engineering. Impedance and mobility are developed as the core analytical tools for predicting the response of structural systems to applied forces and moments. Drive-point impedance formulas for beams, plates, and shells under various boundary conditions are tabulated in a form that the reader can apply directly to engineering calculations.
The concept of mechanical mobility and its reciprocal — impedance — is used to analyze the transmission of vibration across junctions and through structural networks using four-pole or two-port methods. These tools enable the designer to identify structural paths that are disproportionately efficient transmitters of vibration and to evaluate the effectiveness of interventions such as resilient mounts and vibration isolators. The attenuation of structure-borne sound along structural paths, at junctions, and through deliberately inserted discontinuities is analyzed in a chapter that treats both analytical predictions and measurement-based characterization.
The transmission of bending waves across beam-plate and plate-plate junctions receives particular attention, as these junctions are the primary mechanism by which flanking transmission occurs in buildings. The authors derive transmission and reflection coefficients at junctions of various geometries, providing the building blocks for network-level models of structure-borne sound propagation. Sound radiation from structures is addressed through the concepts of radiation efficiency and radiation impedance, showing how the sound power radiated by a vibrating surface depends on both the velocity distribution on the surface and the frequency-dependent coupling between structural and acoustic wave fields.
The critical frequency and the transition from subsonic to supersonic bending wave speed relative to the speed of sound in air are analyzed in detail, clarifying the conditions under which structural elements become efficient sound radiators. A final chapter on the generation and measurement of structure-borne sound addresses practical aspects of experimental work, including the characterization of machinery as structure-borne sound sources and the measurement of vibration transmission in complex structural assemblies. Throughout, the book maintains a high level of analytical rigor while connecting theory to observable phenomena and engineering applications.
It is an indispensable resource for anyone engaged in the design or analysis of buildings, transportation systems, or industrial facilities where structure-borne noise is a performance-limiting factor.