Research On Performance And Application Of Heat-reflective Coating For Asphalt Pavement

As the asphalt pavement has many advantages such as high flatness, low noise, good driving comfort and so on, it has accounted for more and more proportion in road construction in our country. However, asphalt is a heat-absorbing material, solar radiation absorptivity of which is high, reaching 0.8-0.95. In high temperature summer, a lot of heat is absorbed and stored by the asphalt pavement, contributing to the high temperature of the asphalt pavement. The asphalt pavement with high temperature causes two main problems: 1) high-temp erature track disease 2) enhancing heat island effect. According to these problems caused by the high temperature of the asphalt pavement, The paper supported by the term of"Asphalt pavements'solar heat reflective coatings of mechanism research and material development depressing UHI effect, raised a heat-reflecting coating technology which can reduce the temperature of the asphalt pavement by increasing the solar reflection.First, surface heat balance equation was built about asphalt pavement for the endothermic character and the light thermal environment of the asphalt pavement, combining with the reflection characteristics of solar heat-reflecting coating, analyzed the cooling theory of solar heat-reflecting coating; draw the conclusion that solar heat-reflecting coating can reduce asphalt pavement temperature about 9℃in high temperature summer from inside and outside cooling test; Compared with cooling effect of different coating amount, taking economical efficiency into consideration, the coating amount should be controlled within 0.7kg/㎡~0.9kg/㎡ when applied on the asphalt pavement.Then, some relevant pavement performances were researched such as skid resistance, abrasion resistance, temperature-change resistance, water permeability of solar heat-reflecting coating, adhesivity of asphalt pavement and so on. The result of test showed that the coating had good abrasion resistance, adhesivity, temperature-change resistance and had surface layer sealing effect on pavement at the same time, which could reduce water damage effectively. In terms of skid resistance, three different improvement measures have been raised, the measure below was advised: Coating 0.4kg/㎡ paintâ†'spreading 0.5kg/㎡ skid-resistant aggregatesâ†'coating 0.4kg/㎡ paintâ†'spreading 0.3kg/㎡ skid-resistant aggregates.Last, for further analysis about the cooling effect and pavement performance of solar heat-reflecting coating to test and verify the inside research results, this paper studyed on the construction technology and construction quality control of solar heat-reflecting coating, constructed heat-reflecting coating test road. Meanwhile, choosed points to observe the long-term performance of the coating, the result showed solar heat-reflecting coating had good cooling effect,skid resistance and durability.