Damage detection of foundation pile in high-pile wharf based on statistical high-order moment of dynamic response under regular wave excitation

Abstract

Wave is a common environmental excitation of offshore high-pile wharf. It has important application value to use dynamic response under wave excitation to realize damage detection of foundation pile. The existing high-pile wharf damage detection methods are mostly based on dynamic signature. However, due to the special nature of wave excitation, the methods of obtaining signature from dynamic response under wave excitation have noticeable deficiencies both in theory and in practice. In the article, first, the mapping relationship between dynamic response characteristics under wave excitation and local damage was analyzed, and a high-order moment damage detection index was proposed. Second, based on the dynamic response characteristics and the empirical mode decomposition (EMD), a method to extract the effective component of dynamic response was proposed to solve the aliasing of dynamic response in practical engineering. By finite element simulation and experimental model of the high-pile wharf, the robustness and sensitivity of the new damage index were verified, as well as the accuracy and practicality of the new detection method. The proposed method holds promise for effectively utilizing the dynamic response under wave excitation and realizing the routine health monitoring of high-pile wharf foundation piles.