Damage Detection of Concrete Structure Based on Approximate Entropy

A method based on Approximate Entropy (ApEn) Theory is proposed to assess the damaged condition of concrete beams from the vibration signals generated by means of excitation on beams. The presented method no longer concerns about identifying modal parameters of the structures but about estimating the regularity of the time series. Simply-supported concrete beams were monotonously damaged and followed with an investigation of the vibration signals generated from the excitation on these damaged beams. The ApEn method was successfully employed to the generated signals for an assessment of the damage status of concrete beams. In addition, comparative studies between traditional method (Wavelet Transform) and ApEn method show that the latter is capable of capturing the deterioration of these concrete beams with more sensitive characteristics. The ApEn method proposed is of great promise to be applied in real concrete structures.