Abstract
A new closed-open-loop optimal control algorithm is proposed that has been derived by minimizing the sum of the quadratic time-dependent performance index and the seismic energy input to the structural system. This new control law provides feasible control algorithms that can easily be implemented for applications to seismic-excited structures. We developed optimal control algorithms, taking into account the nonlinearity of the structural system and the effect of the time delay, for applying a control force to a structural system subjected to general dynamic loads. These optimal algorithms are simple and reliable for on-line control operations and effective for a structural system with a base isolation mechanism. The control efficiency affected by two weighting matrices included in the performance index is investigated in detail. Numerical examples are worked out to demonstrate the control efficiency of the proposed algorithms.
