Seismic isolation and fuzzy vibration control systems, which consist of a shell with an edge beam which has springs and variable dampers between the edge beam and the ground, are suggested by one of the authors.
In this paper, natural vibration modes and natural frequencies of base isolated rotational shells with edge beams are shown. When the shell shakes due to vertical seismic forces, the seismic isolated system is implemented. As a result, stresses in the shell are significantly reduced.
Furthermore, vibration control of the shell is carried out. Then the damping ratios are adjusted by the fuzzy theory, and stresses in the shell are further reduced.
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