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According to the low temperature disease on asphalt pavement in the areas of cold and large temperature difference between day and night, conventional index test and low temperature bending creep test were used to analyze the influence of diatomite dosage on the low temperature performance of diatomite modified asphalt, and the mixture’s low temperature bending test was applied for verification. Test results show that after diatomite’s addition into asphalt, equivalent brittle point reduces significantly, ductility test cannot estimate low temperature performance very well, stiffness modulus increases and relaxation ability decreases; meanwhile, peak value of stiffness modulus and strain energy of asphalt mixture can be found, the low temperature crack resistance is enhanced; optimum dosage of diatomite is 13%. So, the low temperature performance evaluation method of diatomite modified asphalt mixture through BBR’s low temperature performance evaluation on diatomite modified asphalt remains to be discussed.

Taking modified unsaturated polyester as the matrix resin, methyl ethyl ketone peroxide (MEKPO) and cobalt naphthenate as the redox system, and TiO2, SiO2 and hollow glass beads as the functional fillers, a thermosetting heat-reflective coating with good temperature-reduction effects and wearing resistance, which can be quickly solidified under the room temperature has been produced. In accordance to the research, the amount of solidifying agent and accelerant has great bearing on the gelation time of the coating, and the optimum usage for this system of which will be: 2.5% cobalt naphthenate and 2% MEKPO or 3% cobalt naphthenate and 2% MEKPO; as the increase of the fillers, the temperature reduction effects will be quickly enhanced at the beginning, and then tend to be stable, when the quantity of the fillers is less than 10%, the covering effect of the coating is not obvious, when it is more than 20%, construction difficulties will occur because of the excessive viscosity of the coating. Fillers of 14% with low viscosity and better temperature reduction effect is recommended; as the ratio of TiO2 to SiO2 decreases, the temperature reduction effect of the coating is weakened while the abrasion resistance strengthened and the glossiness reduced; the addition of hollow glass bead can better realize the temperature reduction of the coating, however the glossiness of which will be increased; Colored pigments have slightly negative impact on the temperature reduction of coating. The prepared coating has good abrasion resistance, and can reduce the pavement temperature by almost 10 during hot seasons when it is applied on pavement.

Blends of asphalt and shape-stabilized phase change materials (SSPCM) were prepared by physical blending. Heat storage and thermal stability of asphalt-SSPCM blends were investigated by DSC and TG, chemical compatibility of asphalt-SSPCM blends was characterized by FT-IR, and the application feasibility of SSPCM in asphalt pavement was explored. The results show that asphalt-SSPCM blends have large phase change enthalpy, good thermal stability and chemical compatibility. Based on phase change theoretical analysis and numerical calculation, SSPCM applied in asphalt pavement can actively regulate and control pavement temperature using solar energy conversion or storage, lighten the asphalt pavement diseases related temperatures, enhance the performance of and prolong the service life of asphalt pavement, lower repair and maintenance cost, and enhance driving safety. At the same time, it can also saving energy sources and protect environment. Therefore, SSPCM have broad application foregrounds in asphalt pavement.