Damage detection based on sparse virtual element boundary measurement with enhanced noise immunity under weak formulation

The recently proposed “Weak” formulation of the Pseudo-Excitation (PE) approach was shown to exhibit high noise tolerant ability along with a number of appealing features for identifying structural damages in a thin-walled structure. However, the method requires the dense displacement field measurement in the inspection region. To tackle the problem, a “weak” formulation based on virtual element boundary measurement (VEBM) is proposed in this paper. By dividing the entire structure into several “virtual elements” and tuning the frequency to the natural frequency of the “virtual element”, VEBM allows reliable damage detection by using only a small number of measurement points at the virtual element boundary. The effectiveness of the VEBM was validated numerically and experimentally using a cantilever beam containing a small damaged zone. Results demonstrated that VEBM was able to achieve good detection results by using a small number of measurement points, whist providing enhanced noise immunity capability against measurement uncertainties.