Three-dimensional spectral element simulation of acoustic emission waves and damage location in orthotropic steel bridge decks
According to the fatigue damage evaluation and structural health monitoring demand of orthotropic steel bridge decks of long-span bridges,damage location in large-scale complex plate structures was investigated through spectral element simulation of acoustic emission wave field.Legendre high-order interpolation based three-dimensional time-domain spectral element method was introduced to simulate acoustic emission waves propagating in orthotropic steel bridge decks,where significant reflection,diffraction and dispersion phenomena were observed as expected.Then,abundant acoustic emission data were obtained through spectral element simulation,instead of the manual pencil lead break pre-tests.After that,the Akaike information criterion was used to determine the arrival times of acoustic emission waves at different sensors.A relationship model between the arrival time differences of acoustic emission waves and the coordinates of acoustic emission sources was established by Gaussian process regression,which would be used to locate unknown damages.Numerical simulation results showed that the improved delta-T mapping method based on Akaike information criteria and Gaussian process regression achieved an average location error of 37.3 mm(for the case of 25 dB signal-to-noise ratio)in the orthotropic steel bridge deck,where the location of the plate was more accurate than that in the U-shaped rib.It was demonstrated that spectral element simulation provided a promising approach to substitute the tedious pencil lead break pre-tests and therefore to improve the practicability of acoustic emission damage location based on the series of delta-T mapping methods.
万方数据
维普
