In this paper a particular ON-OFF type of Semi-Active control of the seismic response of braced frames is considered, in which the braces are connected to the frame by special elements, which are activated or deactivated at different times, in order to obtain the best response control. An optimal control algorithm, for n dof systems, is first analyzed and compared with some other ones, presented in the literature, for similar control problems. Comparisons are also systematically made with optimized Passive control strategies based on the use of dissipative connections. It is shown that Semi Active control performs better than Passive; the improvements are only minor in terms of maximum response values, but appear more relevant when the entire time history is looked at.
展开▼
