Research On The Isolation Bearings Of Ellipsoid Shell

Shell structures have diversity structur es, complex modelings, numerous bars and nodes. Currently , the seism ic laws of these structures have not been enough understood and the seism ic design has not yet been fundam entally worked out. Reticulated seism ic and vibra tion r eduction of the shell s tructures are seriously lagging behind in engineering practice. The developing trends of shell structures are more and more com plex in shape s and lar ge-spans at p resent.In this case, the requirements of the seism ic response anal ysis are m ore and m ore higher, m any applications of isolation and vibration re duction measures in sh ell design are also more and more widely used.1. Ellipsoid shell structure m odel wa s established by us ing ANSYS, elastic bearing and damping elastic bearing were sele cted to realize the isolated control. In the state of controlled and non- controlled, the natural freq uencies of ellipsoid shell structure were calculated and the is olated control mechanism of the ellipsoid she ll structure were preliminary analyzed.2 The time-history analysis of shell structures and the numerical calculation of support reaction force and bearing displacem ent in ellipsoid shell were made in rare earthquake.The influence laws resulted by the changes of span ratiosand and span in shell structures were also discussed.3 Analysis of isolation b earings of an ellips oid la ttice shell subjec ted to multi-dimensional earthquake wave has been done here. The bearing reaction forc e and displacem ents with varied bearing pa rameters, which are ho rizontal bearing stiffness, vertical stif fness and d amping coef ficient,are stud ied in deta il.The variation rules and the coupling relationshi ps of various bearing parameters have been carried out. The results provides reference for selecting favorable parameters of bearing in lattice shells.4 In this article, ellipsoid shell modal were analyzed. The natural frequency and the vibration mode of fixed bearings, isolation bearings and the combination isolated bearings with dampers were com pared. The tim e-history analysis of ellipsoid shell under seismic response were made, axis, node displacements, supporting forces and bearing displacements of the two isolation structures were compared.