Seismic stability of vibration-insulated turbine foundations

DOI: 10.37153/2618-9283-2021-5-36-49

Authors:  
Rubric:     Seismic safety and seismic isolation of buildings   
Key words: vibration-insulated turbogenerator set foundation, response spectra, seismic stability, earthquake, seismic isolation, structural dynamics, seismic calculation
Annotation:

The turbogenerator set foundation is a special building structure that unites parts of the turbine and generator unit into a single system and it is used for static and dynamic loads accommodation. The number of designed and constructed power plants in high seismic level areas is large.

Seismic isolation is the most effective way to achieve earthquake resistance of equipment located inside buildings and structures. Achievement of seismic stability power plant turbine foundation by applying a variety of design solutions and seismic isolation systems is a significant issue.

Dynamic calculations were performed in Nastran software using time history analysis and the finite element method. The main criteria for the seismic resistance of a vibration-insulated turbine foundation are the values of the maximum seismic accelerations in the axial direction at the level of the turbine installation and the values of vibration-insulated foundation maximum seismicdeformations of vibration isolators.

The results of computational experiments during investigations allow to estimate the effect of the following factors on seismic resistance of vibration isolated turboset foundations:

- different frequency composition of seismic impact;

- use of vibration isolators of different stiffness;

- accounting of frequency dependence of viscous dampers characteristics;

- use of different calculation methods and computational models. Used Books:

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