Research On Electrical Resistance Tomography Technique For Conductive Concrete Damage Detection

The detection and monitoring technology of concrete health is of great significance to ensure the safety of concrete structures.Electrical Resistance Tomography(ERT)is an emerging computer tomography technology with distinctive features.It has many advantages such as low cost,portability,fast imaging speed,non-pour,etc.,and has broad application prospects in the field of concrete damage detection.The poor electrical conductivity of traditional concrete limits the application of electrical resistance tomography,therefore,this article conducts related research on the electrical conductivity of concrete itself.We write a suitable ERT image reconstruction algorithm and perform computer simulation and experimental verification on it.The main work of this article is as follows:(1)This article conducts relevant research on the electrical conductivity of concrete.We increase the electrical conductivity of concrete by incorporating conductive materials such as graphite to produce concrete with good electrical conductivity,which provides an experimental basis for the application of tomography.(2)This paper conducts related research on the principles and mathematical models of electrical resistance tomography.We use the finite element simulation software COMSOL Multiphysics to perform computer simulation and modeling calculations on the positive problems of electrical resistance tomography.By choosing different parameter conditions(boundary conditions,splitting accuracy)for simulation comparison,the optimal positive problem simulation parameters are determined(3)This paper explores the image reconstruction algorithm of electrical resistance tomography.Based on EIDORS open source code,we independently write inverse problem solving and image reconstruction algorithms on the MATLAB platform,and verify the function of the algorithm through computer simulation.We also wrote reconstruction image quality evaluation software to evaluate the effect of image reconstruction.(4)We propose an image secondary processing method that adds transparency and overlay to the reconstructed image.This program can accurately image the resistivity distribution in an unknown distribution field.(5)We develop a data acquisition system for electrical resistance tomography.(6)This paper explores the dynamic detection ability of electrical tomography for concrete internal damage.Based on the data acquisition system built in this article,we perform experiments on crack damage and hole damage of the prepared conductive concrete,and use the image reconstruction algorithm written in this article to perform image reconstruction.The experimental results show that the electrical resistance tomography data acquisition system and image reconstruction algorithm built in this paper can effectively detect crack damage and hole damage in concrete,and the secondary image processing method proposed in this paper can significantly improve the image quality and accuracy.