Giant - Sub Control Performance Analysis, The Control Structure Under Seismic Excitation

The Passive Mega-Sub Controlled Structural System (PMSCSS) is a new form of structure combined the controlling theory and the conventional mega frame structure, such as tall buildings and super-tall buildings. PMSCSS can achieve controlling displacement responses and acceleration responses of the supertall buildings, because self portions of the buildings (substructures of the buildings) have self-adjusting function. The safety of the supertall buildings can be advanced enormously, under external forces such as winds and earthquakes.PMSCSS is very enormous and complex, the sort and importance of the components structure have obvious classification. So the analysis performance of structure is very difficult, especially under earthquake. The accurate finite element model can analyze accurately the internal force and the mechanics characteristic of components structure, but the time of compute is so long that isn't adapt to the practice of structure engineering. The equivalent frame model of PMSCSS is more predominant for primary structure design and holistic mechanics analysis of structure. According to the assumption that the plane section keeps plane, the equivalent axial rigidity, flexural rigidity and shear stiffness of the super beam and super column were got individually. Thus the equivalent frame model of the super structure was established. The comparison of the result with the precise method indicated that the equivalent model mentioned above is feasible and credible.Following the former study on PMSCSS and consulting the results, the author emphasized on analyzing the seismic behavior under regular and rare seismic, in which make use of step-by-step integration procedure. In analysis, the displacement response and acceleration response of the top megastructure and top substructure are regard as controls parameter.Many factors affect the seismic behaviors of the PMSCSS and the relation among the factors is complex. These factors mainly include RK, ρ_f RM and ρ_k. RK is the rigidity ratio, that is the shear stiffness of substructure to bending stiffness of megastructure; ρ_f is the tuned ratio, that is the natural frequency of the substructure to that of the megastructure; RM is the mass ratio, that is the mass of substructure to that of the megastructure; and ρ_k is the rigidity ratio, that is the shear stiffness of the additional column to that of substructure.In all, the vibration controlling efficiency of the PMSCSS is remarkable and its structural control measures are highly effective. Theoretical studies can serve as references in engineering application.