The Research On Seismic Responses And Vibration Control Of Spherical Reticulated Mega-structures

Applying the concept of reticulated mega-structures to conventional spherical reticulated structures, a new structure which is spherical reticulated mega-structures is put forward to meet the need of space structure into super long span. In this thesis the seismic response of the rib-ring spherical reticulated mega-structures is researched when the structure is in common and severe earthquake. Then the vibration controlling of seismic response is researched by using the viscoelastic damper which is a kind of damper with matured technique. The main content of the thesis are listed as followed:At first, the dynamic equation of spherical reticulated mega-structures is reasearched, including the select of the mass matrix, damping matrix and stiffness matrix. The Newmark time-history analysis method is introduced to analyze the seismic response. The vibration-reduced device is selected based on the theory of energy dissipation.The characteristics of natural vibration frequency of spherical reticulated mega-structure are qutoed in order to illmulate the dynamic charaterstic of structure. The influences of the structural seismic response in different earthquake waves and the differences of seismic response in different dimensional earthquake waves are analyzed. The seismic responses of structure in common earthquake and severe earthquake are researched, and the weakness of structure in the earthquake is founded. At the same time, the effects of the structure control parameters to seismic responses are researched.The viscoelastic damper is used to reduce the seismic responses. The simulation of the viscoelastic damper in ANYSY is researched. Based on the energy dissipation characteristic of viscoelastic damper, the damper is put in the positions where the maximum seismic responses are appeared and some controlling proposals are applied to structure in order to reduce the responses. By analyzing the differences of these proposals in reducing the seismic responses of structure, the best system in vibration controlling is found. The research proved that the controlling system is effective in reducing the vibration, which can disspate the most energy of earchquake.At last, applying the best controlling system to spherical reticulated mega-structures, the seismic responses of structure in serve earthquake is researched by using the time-history method. The variation trend of vibration-reduced coefficient of structure is analyzed, and a series of parameter analysis are carried out for the alteration regularity of vibration-reduced coefficient when the structure control parameters are changed.