Finite element model of concrete material based on CT image processing technology

With the development of concrete performance research, more and more attention has been paid to the study of concrete performance, resulting in a variety of micro-structure finite element models, such as lattice model, beam-particle model, random aggregate model, with the emergence of CT technology, the realization of the non-destructive state of concrete internal micro-structure with digital The rendering method is presented. If the real or near-real finite element model of meso-structure can be established by using the information of CT plane images, it will play a certain role in the numerical simulation of concrete. Concrete includes aggregate, cement mortar and pore three parts, from the image characteristics, aggregate close to white, pore tend to black, cement mortar is between the two. Because of the relative obvious density difference between aggregate, mortar and pore, after CT scanning and converting to image, each component of concrete has better contrast, and it is easier to observe and extract aggregate contour. In this paper, CT image processing technology is used to preprocess the section image of concrete cylinder specimens in order to obtain accurate aggregate geometry and position information. On this basis, the reconstructed micro-finite element model is simulated and simulated in MATLAB, and the results are compared with those of other finite element models. The results show that the finite element concrete micro-model can make up for the shortcomings of the traditional random aggregate concrete model, and better reflect the mechanical characteristics of concrete materials, which opens up a new way for the ultimate in-depth study of the micro-damage mechanism of concrete materials. (C) 2019 Elsevier Inc. All rights reserved.