Theory Of Combined Control System And Its Application In Multistory And Highrise Buildings

The passive control devices used in civil engineering, namely, energy transmis sion, energy dissipation and isolation devices, are different from each other in con trol principles. It is necessary to use some kinds of passive control equipment simulta neously to reduce the responses of multistory and tall buildings when only one device cannot limit the responses within designing indices. Some combined control systems incorporated the advantages of each device in a body are presented in this paperThe study on stochastic structural control in recent only considering wind loads or earthquacke loads, and the stochastic model parameters with personality are sepa rated from practice. Can the stochastic control design for structural seismic and windresistance be according to current design codes? The combined control system of tuned mass/liquid damper (TMD/TLD) and energy—absorbing dampers for multisto ry and tall buildings is discussed in this paper. Taking wind force as the zero—mean Gaussian stationary random process, and the modified random process model of earth quake ground motion corresponding to the Aseismic Design Code GBJ11 — 89 about three level intensity, site soil class and far seismic area, using equivalent lineariza— tion technique for culculating the responses of the structure with and without con trollers, a comparison of the control effectiveness of the combined control system up on wind loads with that under earthquake loading conditions is made. A modal itera tion method for the response analysis of non—proportional damped systems subjected to nonstationary random excitations with arising, stationary, and desending parts is proposed in the paper. The auto— and cross—PSD function matrix of the structural responses is described firstly by means of the complex modal method bcause of the evi dent damping levels of the damping controllers. The non—proportional damping ma trix is divided into two parts: the proportional part for dissipation of energy and the non—proportional part for transmission of energy. The coupled equations in general ized coordinates are solved by an iterative process in which the coupling terms are treated as pseudo—forces. Numerical circulations show the good convergence charac teristics of the process and the good accuracy of the obtained results.