The Study Of Ultrasonic CT On Piles Foundation

In this paper the tomography algorithm of concrete by ultrasonic CT is studied. Because the ultrasonic will refraction when it transmiting in concrete, this paper introducing the ray tracing to tomography arithmetic has improved the reconstruction algorithm and acquired satisfactory results.On the basis of analysing the ray tracing algorithm, the LTI(Linear Traveltime Interpolation)Algorithm Based on Scan-cross is put forward by improving. Because of its omni-directional full scan and only one time in the whole area, the low speed area which is in the same line with emission spot is around, the algorithm precision is improved and the programming complexity is reduced.In the concrete ultrasonic test, due to incomplete sampling data, serious disturbing factors and error,, the algorithm to acquire coefficient matrix A is present, which can reduce the computational difficulty greatly.Finally, the result of numerical simulation shows that make use of the testing method and the reconstruction algorithm in this paper to acquire concrete ultrasonic CT image are feasible and the effect of image reconstruction is satisfactory.This writings proceed some numerical simulation including velocity inversion, ray tracing, graph analysis and division in order to improve the application of CT technique for concrete non-destruction test .In the meanwhile , analyze the graph's characteristic and its factors .