The interest in the ability to monitor a structure and detect damage at the earliest possible stage is pervasive throughout the civil, mechanical and aerospace engineering communities. The thesis focuses on the application of a finite element model updating technique to monitor and detect damage in beams. A Sensitivity Based Element-by- Element (SBEBE) methodology is chosen as the finite element model updating technique. In this method, damage is detected by updating a finite element model with test data obtained from healthy and damaged structures and observing the relative changes in the updated finite element models. The performance, efficiency and sensitivity of the SBEBE algorithm in detecting the damage location and severity are studied through numerical and experimental test cases on a cantilever beam. The location and extent of damage are successfully predicted with all numerical cases. The presence of noise in the numerical data and its effects on the damage detection process are examined. The SBEBE algorithm is capable of detecting the presence, location and extent of damage for noise levels in the numerically generated data up to 5% of the signal amplitude. Also experimental studies are carried out on a cantilever beam with modal data measured using a laser doppler vibrometer. A small section of the cantilever beam is mechanically removed, and the SBEBE algorithm is used successfully to detect the damage location and severity --Abstract, page iii
