Application of modern control theory for building structures

The design of feedback compensators is considered for linear and constant-coefficient multivariable systems and an attempt is made to find a suitable gain matrix for active control of structures. The application of the pole-assignment method is discussed. It is based on the shifting of open-loop poles to the left side of the s-plane, and is applicable to mechanical and electrical systems. The second method developed in this study provides a physical understanding of the active control of civil engineering structures because it allows control of several modes of the system. The K matrix of the control law can be found so that the first few modes of the system have smaller displacements than the corresponding displacements of the original system. Therefore, more modes of higher gain can be used to substantially reduce system displacements. Because the pole-assignment method will not always significantly reduce displacements, the second method is found to be better for the control of civil engineering structures.