Vibrations of industrial structures - Modeling, predictive and interpretation tools

This article makes the deliberate choice of first presenting a number of methods for modeling and predicting vibratory phenomena (§ 1 to ), before describing experimental approaches, considering that today's engineering practice must favor predictive over curative. The maturity of the approaches described is such that any problem properly posed, with the introduction of a few necessary physical quantities, can be solved by calculation, the test often being carried out only as a check, or even substituted for the calculation because it is more economical. On the other hand, a test alone is generally not sufficient to interpret the often highly complex observations of the vibratory state of an industrial structure, and modeling must accompany and support it, predicting the effect of any modifications and thus guiding the designer, installer and operator.

However, if there is any doubt between prediction and reality, the experimental result, if it can be achieved and is not disputable, cannot but impose itself on the engineer. It is therefore the purpose of paragraph 7 and of the article Industrial vibration sensors [R 6 193] to present the full range of measurement and test equipment available on the market, and then, in the fascicule [R 6 192] Vibrations des structures industrielles. Tools and methods for experimental analysis, signal and information processing techniques and a few criteria.

What follows is a description of a set of "tools", whether conceptual tools (i.e. methods) or material tools (i.e. analysis and testing resources), bearing in mind that the engineer, who is generally called upon to carry out remedial work, must not only identify a specific disorder (diagnosis), but also specify corrective solutions: In this case, he or she needs to use diagrams to represent vibratory phenomena, which will enable him or her to identify, qualitatively or quantitatively, the physical...