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In this study, ATH-modified asphalt of different compositions (0wt%, 5wt%, 10wt%, 15wt%, and 20wt%) were prepared for testing. Its flame-retardant performance and dynamic smoke release characteristics were investigated by using the limiting oxygen index (LOI) test and TG-FTIR technology. After pyrolysis, the carbon layer's structure, morphology, and element distribution were analyzed by scanning electron microscopy-energy disperse spectroscopy (SEM-EDS). Adding ATH increased the LOI value of the base asphalt by up to 23.1%. The TG-FTIR results showed that ATH significantly improved the flame-retardant performance of asphalt through three physical effects: cooling, dilution, and heat insulation. Adding ATH to asphalt affected adsorption and blocking, thus reducing smoke, promoting carbon formation, and improving its smoke suppression. Observations of the microscopic carbon layer showed that incorporating ATH improved the integrity and strength of its structure. Based on these results, a mechanistic model of the flame retardancy and smoke suppression of ATH-modified asphalt was established.

Due to the typhoon impacts, aquaculture net cages may be exposed to the risk of structural failure as a far-reaching aquaculture equipment. In addition, the fatigue problem of key components due to long-term marine alternating loads can not be ignored. The method is developed independently on processing samples of cage for testing its performance parameters, among which the fatigue Wohler curve is S= -1.022ln (N) + 22.201. By adapting the following methods: Mechanical test, Equivalent load finite element simulation and Full field finite element simulation respectively is verified each other, and the error is less than 5%. The key nodes of the stress concentration of the floating frame are mainly the welding point, the mooring point and the edge area of the I-beam frame at both sides. The damage of the cage which caused by tensile and bending loads should be considered at the same time. And the tensile strength 22.12 MPa and the bending strength 30.58 MPa could be taken as the evaluation standard for the elastic to plastic deformation. Structural fracture occurs when the elongation at break exceeds 340.18%. The fatigue of the cage is mainly because the stress is much greater than the fatigue limit 3.38 MPa. The material model test combined with structural mechanics simulation provides the basis for guiding the structural optimization design of the cage.