Research On Location And Quantification Of Concrete Structural Defects Based On GPR Images

Ground penetrating radar(GPR)is a developed technology for nondestructive inspection recently.Compared with the traditional detection methods,GPR technology has the advantages of high efficiency,low cost and better resolution imaging.The traditional GPR data interpretation relies on manual mostly,which is subjective and inefficient.In this context,this paper studies and implements a set of schemes to support the automatic location,classification and quantification of defects in concrete structure.The specific research contents are as follows.(1)GPR image interpretation based on disease feature analysis and classification lack of training set.In this paper,gpr Max is used to simulate the void and delamination in the concrete structure and analyze the physical characteristics.For the first time,a method of defect location based on template matching is proposed.Firstly,the AOI(area of interest)of GPR data is screened by row variance algorithm.Secondly,AOI is enhanced by histogram equalization and trinization.Finally,according to the characteristics of the wave on the dielectric difference surface,the AOI without defect is filtered and the connected areas with high matching degree are selected as the defect location.(2)For the first time,a method of defect classification and quantification based on Hough transform and curve analysis is proposed.Firstly,Hough transform is used to extract the hyperbolic features of the defects,and identify the void,void with water and delamination through curve analysis.Finally,according to the known defects types,the physical parameters are quantified.The results show that the error of physical parameters quantified by curve analysis and F-K migration algorithm is less than 20%.(3)Finally,the overall scheme is tested by the GPR data in the tunnel and road inspection,the test results verify the stability and reliability of the algorithm.The validation of simulation and real data shows that this GPR data interpretation scheme can identify the three main defects in concrete structure,and carry out positioning and quantification effectively.The experimental results meet the needs of GPR image automatic interpretation in engineering practice.