The Application Of Image Analysis Technology In Granular Material Fabric Image Measurement

Granular material is the main material of embankment dams and is one of the major study objectives of soil mechanics. The rheology problem of high earth rockfill dam has been widely contemplated by experts and engineers specialized in dam engineering,and the rheology property of coarse stuff adopted as the stuff material is the base of research. But so far, studies in this area are relatively few. As a kind of coarse aggregate,it was shown that the arrangement and intergranular action of particles had important impact on the mechanical property of granular material and many problems related to the granular material fabric.The principal achievements of the fabric research of granular material were presented.This dissertation firstly raises a point that from the perspective of image analysis, through MRI(Magnetic resonance imaging) technology,to observe the dynamic change of granular material internal structure during the process of force and deformation.The Longitudinal section image of granular material shows the situation under pressure well.Segmentation is a key step during the particle image processing.The segmentation result has direct influence on the counting accuracy and the following processing. Each particle will be extracted as a goal for form information analysis,and further,the situation of the interaction between the particles will be studied.According to the characteristics of images, the optimal thresholding method is used to get binary image. The boundary of particles is generally accurately determined.But we can find some particles tend to cluster into each other.So According to larger curvature of Crosspoint,Harris corner detector is selected to separate the clustering particles because the algorithm is stable, not sensitive to noise.Finally Motion Image of Granular Material Fabric Measurement System is achieved to analyse quantitatively the element of the fabric and provide a good support for mechanical effects analysis of fabric and the establishment of mechanical model.