The Construction Of Cement Microstructure Based On VTK And Random Sequential Adsorption

As one of the major basic construction materials, cement material has been widely used in industry, agriculture, transportation, urban construction, water conservancy and marine development etc. Cement material is in a prominent position in the development of economy and society. Meanwhile, the cement products show the superiority on replacing the steel and the wood. Therefore, to improve the performance of cement material is very important for the development of the national economy and the national construction. The characteristics and properties of the cement are affected by the microstructure of cement. Thus, it is very significant to research the microstructure of the cement in order to improve its performance.With the advancement of computer science and technology, especially the development of scientific visualization technology, it is possible to research the microstructure of cement. Visualization Toolkit (VTK) is an important tool in the field of three-dimensional reconstruction owing to its powerful features, convenience and opening source code. In this paper, we use the advanced visualization tool VTK to achieve the three-dimensional reconstruction of the cement particles based on the Visual Studio 2005 development platform. And on this basis, we combine with the random sequential adsorption (RSA) method to distribute the cement particles, thus we can establish the microstructure model of cement. The main contents are as follows:First, we need to obtain the two-dimensional sectional images of cement firstly before the three-dimensional reconstruction of cement particles. In this paper, we use X-ray tomography to get several sectional images of cement. According to the characteristics of the images, they are handled by the threshold method and region-growing algorithm. Ultimately the sectional images of a single cement particle are separated, thereby it paves the way for three-dimensional reconstruction of cement particles.Second, the reconstruction of cement particle is realized by the ray-casting algorithm. At first, we read in several sectional images of a single cement particle. Then the cement particle is reconstructed by maximum intensity projection and composite methods which are provided by VTK as the ray-casting algorithm. Finally we get the real cement particle. Experimental results show that ray-casting algorithm is better to draw the cement particles and many details are retained. At the same time, the rendering speed is very fast, it can be completed only in a few seconds.Third, we research the basic principle of the RSA algorithm and the concept of bounding box. The current methods to achieve RSA algorithm exist some problems, such as the difficulty of distributing the three-dimensional objects, huge amount of calculation and the slow speed. Combining with the irregularity of cement particles, this paper proposes a new method to achieve the RSA algorithm. The essence of this method is that the operation of three-dimensional is reduced to two-dimensional. Firstly the sectional images of cement particles are processed by bounding box technique before they are randomly distributed in the two-dimensional space. Then we can obtain several images of distributed cement particles, thus the three-dimensional volume data are formed. At last, we use VTK to visualize them in order to obtain three-dimensional microstructure model of cement. Experiment results show that the execution time of RSA is reduced and the microstructure model with specified number of cement particles can be established.