Increasingly, structural engineers are encountering vibration problems in a range of structure types resulting from many forms of stimuli. Often the most severe serviceability criteria are those concerning human response to structural vibration or for interference with delicate instrumentation. The vibration may be impulsive, from events such as blasts or impacts, transient from passing traffic or movement of materials, continuous from machinery or services, or may be infrequent, random motion with a return period in terms of months or years for events such as storm winds. In many instances the vibration is accompanied by intrusive noise, or in some cases infrasound may induce motion sensation in humans, such that the subjective response of the people involved must be assessed not independently to noise and vibration but in one evaluation since the response is governed by each of the actions inextricably combined. Guidance is available for determination of probable human response to single or multifrequency linear vibration in one or several directions. An assessment method for human response to combined translational and rotational motions is also currently in use but, to date, methods for estimating the subjective response of humans to combined noise and vibration environments are not available.
A.W. Irwin