EFFECT OF TIME-DELAY ON CONTROL OF SEISMIC-EXCITED BUILDINGS

The sensitivity of a system time delay with respect to the performance of control systems for seismic-excited buildings is examined. The effect of a system time delay depends on the particular control algorithm and the particular control system used. Four control algorithms feasible for applications to conttrol of seismic-excited buildings have been studied. These include the linear quadratic optimal control algorithm and three instantaneous optimal algorithms proposed recently. The sensitivity analysis for each control algorithm is performed using a simulation approach. Both the active tendon control system and the active mass damper have been considered, and the tall building is idealized by a shear-beam lumped-mass discrete system. Numerical examples are worked out to demonstrate the criticality and tolerance of a system time delay for each control system. It is shown that a time delay always results in a degradation for the efficiency of a control system and that the tolerance for a system time delay is quite stringent for cases investigated. © ASCE.