Stiffness identification of framed models using modal data

National audienceThis article presents the experimental evaluation of a reduced scale framed building model subjected to dynamic tests and controlled damage conditions. In the first part of this article, stiffness identification procedures are developed, and two methodologies are presented: when the mass matrix is known or when it is unknown. In this last case, the mass matrix must be identified before the stiffness matrix is assessed. The identification procedure requires an experimental essay as well as an analytical model to establish the initial undamaged condition of the structure. In the second part of this article, the frame building scale model and the performed experimental tests, leading to the dynamic identification of the structure, are described. Various controlled damage conditions of the structure are considered, and their dynamic properties are evaluated by experimental means. The proposed identification procedures are then applied and the results are discussed. Both methods prove to be suitable to successfully identify the damage location and the stiffness matrix of the structure under various damage conditions