87-0007 Instantaneous Optimal Control Laws for Tall Buildings Under Seismic Excitations J.N. Yang, A. Akbarpour and P. Ghaemmaghami 1987 George Washington University 106 PB88-134333 0 A critical review of classical optimal control algorithms is made with respect to the specific application of structural control under seismic loads. With the earthquake ground acceleration being the major source of continuous external disturbances, the Riccati closed-loop control does not satisfy the optimal condition. New optimal control algorithms are proposed herein including the instantaneous optimal open-loop control, instantaneous optimal closed-loop control and instantaneous optimal closed-open-loop control. These new control algorithms are aimed at developing feasible control algorithms that can easily be implemented, for applications to seismic-excited structures. Numerical examples are worked out to demonstrate the control efficiency of the proposed control algorithms. (Authors' abstract). Tall buildings. Seismic excitations. Structural control. Optimal control algorithms. Random vibrations. Tendon control systems. Mass damper systems.