Investigation of pile-integrity using novel signal processing methods

Paper in proceeding, 2009

As there are a lot of limitations on health monitoring of piles, stress wave propagation tests are of interest among civil engineers and researchers. In these methods, the testing signal recorded by receiver on the pile head should be analyzed to check whether any defect exists. In this paper, the application of low strain pile-integrity tests and interpretation of the results by Continuous wavelet transform (CWT) is studied. Finite element model of some imaginary piles are provided in order to analyze the response of the structures due to a known signal. The results demonstrate that the testing signal can be broken down into time and frequency domain at the same time. As a result, more characteristics of the testing signal can be depicted, and defects can be detected easier than the traditional signal processing methods, such as Fourier transform (FT). Furthermore, the results show that impedance is not a proper criterion to identify damage severity, and damage detection ability of low strain test is a function of defect length as well.