Comparative Study on FFT and MEM in Identifying Concrete Defect Size by Impact Echo Method
Aiming at two signal analysis methods for identifying concrete defect size by impact echo method,the application of FFT and MEM in impact echo signal processing was studied through theoretical analysis and field model test.The results show that the FFT algorithm is simple and fast,but adding window functions during the analysis process can lead to spectrum leakage and reduced resolution;The MEM algorithm can reasonably estimate signals outside the known data,and it has higher resolution,which is more in line with the requirements of practical engineering;The spectrum and predominant period can carry defect information,which is reflected as peak advance in FFT calculation results and peak delay in MEM calculation results;The contour map can more intuitively identify the presence of defects,and the calculation results of MEM have higher accuracy than those of FFT.
万方数据
维普
