This research addresses the problem of stability or safety of structures which is one of the most important design considerations, particularly for those which are vulnerable to high winds or earthquake excitations. One primary stability factor is the P- effect produced by an overturning moment dependent on the floor gravity load and the floor rotation. One possible approach to this problem is to make use of the concept of structural control in preventing undesirable, excessive P- stresses induced by external excitations. The research aims at investigating the feasibility of such a stability control concept and establishing a theoretical base for control systems. Both passive and active control systems, including mass damper systems and tendon systems will be studied. A state vector approach will be used to provide the mathematical framework of the analysis which will incorporate the treatment of P- effects using a plastic hinge idealization and a model which allows for a gradual development of yielding in highly stressed regions of structural members. This study will contribute to the practical implementation of control systems in the safe construction of the engineering facility. This is a research initiation grant under the Research Opportunity for Women program supported by the Engineering Directorate.
