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The permeability coefficient of concrete was tested by self-made falling water test device, and the relationship between porosity and permeability coefficient was analyzed. Based on the design of plugging test, the influence of different particle size blockers on concrete plugging and the plugging process of yellow mud that is sticky on concrete were studied. The results demonstrate that there is a high linear relationship between the porosity and the permeability coefficient; when facing the same size of blocker. the anti-clogging ability of concrete with different voids is different, the size of blockage sensitive particle of concrete with 15% porosity is 0.15~0.3 mm and 0.3~0.6 mm, while that of concrete with 20% and 25% porosity is 0.3~0.6 mm and 0.6~1.18 mm; the concrete with different voids was blocked seriously by graded gravel, the sticky blocker such as yellow mud would lead to the rapid plugging of permeable concrete. [ABSTRACT FROM AUTHOR]

In order to analyze the rationality of evaluation indexes HI1, HI2, HI3, HI4 and HI5 based on rheological properties for self-healing performance of asphalt, DSR (dynamic shear rheometer) is used to test the relationship between the complex modulus and loading times of virgin asphalt, SBS modified asphalt and rubber modified asphalt. Based on four-point bending fatigue test, the fatigue-self-healing properties of virgin asphalt mixture, SBS modified asphalt mixture and rubber modified asphalt mixture are studied. The results demonstrate that evaluate the self-healing performance of asphalt with different indicators may obtain different results, the order of self-healing ability of virgin asphalt, SBS modified asphalt and rubber modified asphalt is inconsistent, and the evaluation result of HI5 index on self-healing ability of three asphalts is consistent with mixtures, the self-healing ability of rubber modified asphalt and SBS modified asphalt is better than virgin asphalt obviously. [ABSTRACT FROM AUTHOR]

In this paper, fluorescence microscope was used to analyze microstructure of A-70' asphalt, SBS modified asphalt and rubber modified asphalt, and DSR was used to test and evaluate self-healing properties. The results show that the higher the temperature is, the more the SBS modifier, rubber powder and matrix asphalt tend to be phase soluble, and the solubility of SBS and 70' asphalt is better than that of rubber powder. The self-healing capacity of SBS modified asphalt and rubber modified asphalt is comparable and better than that of A-70' road petroleum asphalt. The self-healing property of asphalt material is inversely proportional to the degree of injury. The greater the degree of injury, the less significant the self-healing ability. The self-healing energy barrier of rubber modified asphalt is the largest, followed by SBS modified asphalt, and 70' asphalt is the smallest. The self-healing effect of rubber asphalt requires higher temperature conditions and heat supply. [ABSTRACT FROM AUTHOR]