INDUSTRIAL MACHINES AND EARTHQUAKE EFFECTS OF FOUNDATION

Improvement in manufacturing technology has provided machines of higher ratings with better tolerances and controlled behavior. These machines give rise to considerably higher dynamic forces and thereby higher stresses and, in return, demand improved performance and safety leaving no failures. This paper highlights need for a better interaction between foundation designer and machine manufacturer to ensure improved machine performance. The paper also describes the design aids/methodologies for foundation design. Various issues related to mathematical modeling and interpretations of results are discussed at length. Intricacies of designing vibration isolation system for heavy-duty machines are also discussed. Influences of dynamic characteristics of foundation elements, viz., beams, columns, and pedestals etc. on the response of machine, along with some case studies, are also presented. The paper also touches upon the effects of earthquakes on machines as well as on their foundations. Use of commercially available finite element packages, for analysis and design of the foundation, is strongly recommended, but with caution.