Characteristics Extraction And Fractal Research Of Mortar Mortar Anchor Solid’s Corrosion Morphology Based On Digital Image Processing

Anchor is a reinforcement measures that widely applied to geotechnical, some corrosive factors in environment makes the bolt’s macro mechanical performance degenerated, and macro mechanical properties of mortar anchor changes with microstructure. What changes have happen in microscopic structure, how to measure these changes, this is a problem to be solve. This paper use the digital image of mortar bolt corrosion experiment to extract the mortar anchors’ macroscopic and microscopic morphology characteristics through image processing technology, and use fractal theory to quantitatively describe the appearance characteristics, and established the relationship between the fractal dimension the interface bonding strength of the mortar anchor, the main work and achievements are as follows:①The image of macroscopic morphology characteristics is pre-processed by various methods, and select the most appropriate method. Using the morphological opening and closing operation to process the isolated point and burr, and eventually extracte macroscopic morphology characteristics from the image.②Using fractal geometry method to do fractal research of macro cracks’ binary image, and found that with water cement ratio increases, the crack fractal dimension increases, bond strength of crack fractal dimension and mortar anchor approximately negative linear relationship, with the fractal dimension increases at different water cement ratio, the bond strength of mortar anchor decreased gradually.③The micro SEM image of mortar bolt corrosion is pre-processed through various means, and this paper counts the microscopic pore characteristics of mortar under different corrosive conditions, and found that with corrosion time increasing, the porosity of anchor under force conditions or non-force conditions is linearly increasing, pore number decreases gradually with the etching time increasing, and average pore size increased with the etching time increasing; the bond strength of mortar anchor under force conditions or non-force conditions is increasing as the porosity decreased.④Using the method of fractal geometry research the characteristics of micro pore, and found that with the increase of corrosion time, the pore fractal dimension gradually reduce, the relationship between fractal dimension and porosity are almost negative linear, the bigger the fractal dimension, the lower the porosity; At the same time, this paper also established the connection between the fractal dimension and the macroscopic mechanical properties, the relationship between fractal dimension and the bond strength of mortar anchor is main approximation linear, with the increase of fractal dimension, the bond strength of mortar anchor also gradually increased.⑤Through the pressure mercury test and the scanning electron microscope SEM image processing results, it is found that the change of pore features is basically the same, but the porosity of SEM image processing is bigger than the former.