<p>«Vibrations in Structures» concentrates on vibrations in structures as excited by human motion or machine operation. Man-induced vibrations may arise from walking, running, skipping, dancing, etc. They occur mostly in pedestrian structures, office buildings, gym­nasia and sports halls, dancing and concert halls, stadia, etc. Existing publications treat by and large some isolated aspects of the problem; the present one attempts, for the first time, a systematic survey of man-induced vibrations. Machine-induced vibrations occur during the operation of all sorts of machinery and tools with rotating, oscillating or thrusting parts. The study concentrates rather on small and medium size machinery placed on floors of industrial buildings and creating a potential source of undesirable vibrations. The associ­ated questions have rarely been tackled to date; they entail probiems similar to those of man-induced vibrations.</p> <p>The book is consciously intended to serve the practising structural engineer and not primarily the dynamic specialist. It should be noted that its aim is not to provide directions on how to perform comprehensive dynamic computations. Instead, it attempts the following:</p> <ol> <li>to show where dynamic problems could occur and where a word of caution is good advice;</li> <li>to further the understanding of the phenomena encountered as well as of the underlying principles;</li> <li>to impart the basic knowledge for assessing the dynamic behaviour of the structures or structural elements;</li> <li>to describe suitable measures, both preventive to be applied in the design stage and remedial in the case of rehabilitation.</li> </ol>