Giant - Sub Frame Damping Wind-induced Vibration Of The Structural System Initiative, The Hybrid Control Simulation Analysis

Mega-sub frame controlled structural system proposed by Maria Q.Feng and Akira Mita who combined structure control theory with the characteristic of conventional mega-sub frame structure is a new structural configuration of super tall buildings. It ingeniously applies the principle of tuned mass damper and multiple tuned mass damper to the structure, thus appears as a structural system having self-control function.Based on the former's study, this paper takes work on the active and hybrid control of mega-sub frame controlled structure aimed at improving the safety and human comfort. In order to testify the validity, this paper also carries out the emulation analysis of dynamic response about a computation example under wind load.Cantilever bending stiffness is adopted in the mega structure, and shearing stiffness in the sub structure. Using the lumped mass model, this paper establishes the wind-vibration analytical model of mega-sub frame controlled structure and expresses its concrete form of dynamic equation. The pulsating wind load of mega structure in along-wind direction is simulated according to M.Shinozuka method related to deduction of pulsating wind pressure specification spectrum and calculation of pulsating wind load spectrum. The analytical model of active control is established and the optimal control force is deduced based on the classical LQR optimal control theory. This paper also puts forward a new hybrid control system which combines the active control with adjusting the structural parameter and analyses the system with the optimal control theory. There are two methods: the combination of active control with adjusting the relative stiffness ratio and combination of active control with adjusting the relative mass ratio between the mega and sub structure. wilson -θ method is applied to time history analysis of active and hybrid control.Choosing an engineering as emulation example and fixing the form of weighting matrix in terms of energy, this paper discusses the weighting parameter to be confirmed and adjusting parameter how to influence the control effect of the displacement response at the top megamass and the acceleration response at the top submass, at the same time how to influence the maximal control force. Then the optimal parameters are decided on and used to explore how to influence else part of structure. This paper involves in comparison between different active control systems, between active and hybrid control, and between two hybrid control methods etc.