Damage detection via substructural analysis

This paper proposes a method to assess the conditions of a substructure by simultaneously identifying the interface forces between substructures and detecting local damages in a selected substructure from the dynamic response with the structure under support excitation. The substructure is subject to a set of interfacing forces at the interface degrees-of-freedom. These interfacing forces between substructures are represented by orthogonal functions, and a sensitivity-based method is then used for identifying the interface forces and detecting local damages of substructure. A five-storeys plane frame structure is taken as an example for validating the proposed method. Numerical simulations with noisy measured accelerations show that the proposed method can accurately identify the interface forces and detect local damages of substructure without the inclusion of other substructures.