Active control of seismic-excited buildings

An investigation is made of the possible application of both the active tendon and active mass damper control systems to buildings excited by strong earthquakes. The effectiveness of both active control systems as measured by the reduction of coupled lateral-torsional motions of buildings is studied The earthquake ground acceleration is modeled as a uniformly modulated non-stationary random process. The problem is formulated using the transfer matrices approach and a closed-loop control law The random vibration analysis is carried out to determine the statistics of the building response and the required active control forces. The method of Monte Carlo simulation is also employed to demonstrate the building response behavior with or without an active control system. A numerical example of an eight-story building under strong earthquake excitations is given to illustrate the significant reduction of the building response by use of an actives-tendon or an active mass damper control system.