Pattern Matching-Based Structural Damage Identification Using Mode Shape Difference Ratio with Limited Sensors

In order to rapidly identify structural damage, a pattern matching-based structural damage identification using mode shape difference ratio with limited sensors is proposed. The mode shape difference ratio is proposed as the damage indicator for pattern matching. The natural frequencies and mode shapes of the structure under different damage scenarios are obtained by the numerical simulation with finite element software. Using the simulation results, the damage pattern library based on mode shape difference ratio matrix is constructed. Afterwards, for the real structure to be test, the response power spectrum ratio is calculated with the measured acceleration responses. Then the mode shape difference ratio matrix of real structure is constructed using the power spectrum ratio of the measured responses with limited sensors. With the reciprocal of correlation coefficient difference (ROCCD) used as the pattern matching approach, the actual structural damage pattern is matched with the pattern in the damage pattern library. The pattern in the library corresponding to the maximum value of ROCCD is considered to be the damage condition of the structure. Finally, the numerical simulation and experiment of a four-layer interlayer shear model are investigated. The results show that the proposed method well determines the damage location and severity of the structure, and possesses excellent practicability.