The Research On Detection Method Of Asphalt Pavement Core Samples Based On Digital Image Processing

With the continuous development of science and technology，the materials, structureand paving method of the asphalt mixture pavement developed rapidly. Detecting thepavement core samples to evaluate the material and performance of asphalt mixture is stillthe main method of road detection. Core sample test is a fast, intuitive and effective meanfor the asphalt mixture detection.The main purpose of the study is to obtain the cross-sectional view of the core sampleof the asphalt pavement by using the method of X-ray computerized tomography or digitalcamera, etc. And use the image processing technology for image graying, image enhanceand image binary segmentation, then to identify the aggregate, asphalt mortar and voids inthe cross-sectional image of the specimen, and extract the porosity, voids characteristics,and analysis the aggregate gradation and evenly characteristics of the asphalt mixture.Established the discrete element model based on the digital image to simulate the indirecttensile test, and obtained the following results.1）Take sectional photos for the core samples of the asphalt mixture pavement usingthe X-ray computerized tomography or digital camera. Using the digital image processingtechniques to process those sectional photos. Summarized the processing methods and pathwhich suitable to the sectional photos of the asphalt mixture pavement.2）Introduced the stereo theory, calculated the three-dimensional distribution of theaggregate by analyzing the two-dimensional information in the cross-sectional view of theasphalt mixture specimen, and through contrast the three-dimensional distribution resultswith the design ratio, deduced the correction factor of the asphalt mixture aggregate, thento calculate the composition of the asphalt mixture by using the digital image processingtechnology.3）Calculated the porosity of asphalt mixture, described the void characteristics,evaluated the transverse uniformity and vertical uniformity of the aggregate in the asphaltmixture core sample by processing the sectional view of the core samples. And proposed a new evaluation method.4）Reconstructed the digital specimen of the asphalt mixture based on digital imagetechnology, and simulated the Indirect tensile test of the asphalt mixture. Analyzed theMicro-mechanical properties and force distribution results of the asphalt mixture.