Structural damage detection using the polynomial annihilation edge detection method

It is well-known that damage in a structure may cause a discontinuity in mode shapes or their derivatives, which has been used as a basis for some damage detection approaches. However, if the severity of damage is small, the discontinuity will be difficult to be detected. The polynomial annihilation edge detection method improves the accuracy of localising discontinuity in a function by determining intervals of smoothness in the function. The feasibility of this edge detection method in localising and quantifying cracks in a cantilevered beam has been demonstrated (Surace et al, 2013). This study is to further validate this edge detection method on various types of structures and damages using numerical simulations. First, this method is performed on a cantilever aluminium bar under longitudinal vibrations to localise and quantify cracks; then, it is performed on a simply supported steel beam to detect cracks. Finally, this method is applied to a more complicated structure, a cable-stayed bridge model, to localise the damage occurring in girders.