Preparation And Performance Evaluation Of Solar Heat Reflective Coating On Asphalt Pavement

Asphalt pavement occupies a large proportion in highway and urban road paving. Insummer，the temperature of asphalt pavement can often reach over60℃,since the constituentmaterials of asphalt pavement possess high rate of solar heat radiation absorption. Theexcessive temperature can not only result in diseases of asphalt pavement，as well as intensifythe urban "heat island effect". Domestic and foreign researchers have carried out thecorrelational researches for the high temperature hazards of asphalt pavement and raised sometechnical measures in which, improving the albedo of pavement is an effective way of coolingtechnology and is still developing in China. According to domestic practical conditions, thesolar heat coating which use for asphalt pavement is developed and the performance is furtherdiscussed.In the first place, according to the basic principles of heat transfer and meteorology, thefactors which effect on temperature of asphalt pavement were analyzed and the resultsshowed that increasing the albedo of asphalt pavement can effectively reduce the temperatureof the asphalt pavement，and ease the urban “heat island effect”.The cooling and environmentimproving mechanism of of solar heat reflective asphalt pavement was analyzed, and thecorresponding technical requirements based on the performance of material were put forward.And then, the cooling effect of domestic common functional materials were tested andanalyzed by independently developing indoor cooling test platform and the optimizedcomposition were developed. The soalr heat-reflective coatings used for asphalt pavementwere prepared and tested. The results showed that the coating possess a good cooling effectand proposed the method of predicting outdoor cooling effect by the laboratory test methods.The performance of slid and milling resistance of solar heat-reflective asphalt pavement werestudied and the results showed that the two anti-skid particles meet the non-slip requirements,and have less impact on the cooling effect, but the performance of wear resistance is different,and should be choice reasonably in practice. To prevent the glare performance ofheat-reflective pavement, MATLAB software was proposed to evaluate the correspondingcolor lightness value. Finally, time hardening creep model was used to simulate the rut depth of asphaltpavement under different temperature conditions by the ANSYS and the results showed thatsolar heat reflective coating can effectively cool down at the least10°C and the coatingprepared in this paper meet the requirements of rutting resistance. Road effective radiationformula to Calculated the heat transferring from solar heat-reflective asphalt pavement andcommon asphalt pavement to the near-atmosphere, the heat of solar heat-reflective asphaltpavement compared to common asphalt pavement reduced of43.6%, that will significantlyease the urban "heat island effect ".