Abstract：To analyze the characteristics of porous asphalt pavement in micro-perspective way,X-ray CT technology was used to obtain the internal images of PAC-13, and the image closest to the real gradation was selected to extract aggregate and void structure by stereology after image segmentation. The discrete element model (DEM) was established with pixel side length of 05 mm, and the uniaxial compression virtual experiment was carried out. The results show that the gradation error of 3D reconstructed slice image is nearly 20％ smaller than that of transverse scan image, and the reconstructed slice image gradation is more representative. The compressive strength of virtual uniaxial compression test performed by the model is less than 3％ different from that of real uniaxial compression test. The model has good reliability,which can provide research basis for studying the internal mesoscopic structure of porous asphalt concrete.
马翔1, 袁则瑜1, 陈满军2， 周培圣1. 基于数字图像的大空隙沥青混凝土离散元模型[J]. 江苏大学学报（自然科学版）, 2019, 40(6): 734-739.
MA Xiang1, YUAN Zeyu1, CHEN Manjun2, ZHOU Peisheng1. Discrete element model for porous asphalt concrete based on digital images[J]. Journal of Jiangsu University(Natural Science Eidtion)
, 2019, 40(6): 734-739.
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