Study on Improved Computed Tomography Algorithm in Concrete Structure

Abstract

In ultrasonic CT of concrete structure, ray tracing technology based on SNELL principle is far more meet the characteristics of ultrasonic propagation. Inversion algorithm of tomography imaging is to solve large sparse equations. Simultaneous iterative reconstruction technique (SIRT) algorithm solves the problem from the mathematical view. According to engineering application, A improved imaging reconstruction method is proposed in the basis. During the data processing of simulation, the data weighting matrix is introduced to increase the proportion of effective information firstly; And then the units without ray passing through is merged with its adjacent units so that the slow-wave in reconstruction section could be changed smoothly by using unit merger method and ensure high resolution in middle section; And finally the image of CT reconstruction is obtained. Simulation results show that the improved algorithm is effective and could meet engineering requirement.