Preparation and performance evaluation of epoxy-based heat reflective coating for the pavement

Abstract

Abstract. According to the basic characteristics and composition of heat-reflective coating, combining with the functional requirements of road materials, the experiment selects the epoxy resin with good wear resistance and adhesive force as a film forming material, with TiO2, SiO2 and extinction powder as the main functional filler. The experiment gets a good formula with suitable viscosity, low glossiness and good cooling effect, optimizes by orthogonal experiment. The experiment evaluates the indoor and outdoor cooling effect of heat-reflective coating, and analyses the road performance of the coating. The results shows that the better heat-reflective coating formula included 12% of titanium dioxide, 4% of silica and 4% of extinction powder. When the dosage of coating is 0.8kg/m2, the indoor specimen of heat-reflective coating decrease the temperature of 12 ~ 14℃, and the specimen under solar radiation can reduce the temperature of 7 ~ 9℃. The pavement of heat-reflective coating has good wear resistance, but the road slip resistance partly declines. Therefore, it needs to add the anti-sliding particles to meet the safe driving requirements. IntroductionThe characteristics of heat absorption and temperature sensitivity can easily lead to pavement rutting, cracks, loose, bleeding and other diseases to asphalt pavement. This has greatly limited the application of asphalt pavement, and the high temperature of asphalt pavement will aggravate the formation of urban heat island effect. At present, the main measures to solve the high temperature disease of asphalt pavement are adjusting the asphalt mixture gradation, improving asphalt grading standards, expanding the application range of modified asphalt, and adding modifier in asphalt mixture. These measures have improved the high temperature performance of asphalt pavement to some extent. But the problem of high temperature does not be solved radically. As a new mode of active cooling, the solar heat-reflective coating has received more and more attention. People did a lot of research on it. Many researchers tried to use Silicone-Acrylate Emulsion, Acrylic Resin and Unsaturated Resin as binder resin to make heat-reflective coating, and applied it to asphalt pavement. But due to the vehicle friction, the coating appears different degrees of damage after a period time of application. Based on this situation, the experiment makes a heat-reflective coating which has good wear-resisting performance and cooling effect. The main content of this paper is about epoxy resin has good wearresisting and that adhesion as film forming material. Meanwhile, TiO 2 , as the main reflective material and SiO 2 as material improves coating's wear-resisting performance.

Development of Super Road Heat-Reflective Coating and Its Field Application

“…The temperature difference between each sprayed sample and the control was used as the index to evaluate the cooling effect of the coating. Sunlight exposure was simulated using iodine-tungsten lamps [17,23]; the temperature data were…”

“…Outdoor tests and experiments on test sections have also been conducted to further confirm the cooling effect of heat-reflective coatings [7,10,20,21]. Furthermore, Jiang et al reported that heat-reflective pavements have better stability at high temperatures [17,22,23]. This excellent cooling effect is one of the main reasons for the rapid development of heat-reflective coatings for asphalt pavements; in addition, the convenient construction and low cost of heat-reflective coating [5] have made them one of the best solutions to rutting damage and heat island effect caused by asphalt pavements in summer [4,17,22,23].…”

“…Road researchers have studied not only the cooling effect of these coatings, but also the skid resistance, aging performance, permeability, microstructure, and abrasion resistance of the resulting heat-reflective pavements, as these coatings are applied to asphalt pavement surfaces. Cao et al verified the reduced anti-skid performance of heat-reflective road surfaces [7,17,[23][24][25][26], and reported that a controlled dosage of heat-reflective coating within 0.8 kg/m 2 can still satisfy the Technical Standards of the Chinese Technical Specifications for Construction of Highway Asphalt Pavements (JTG F40-2004) [27]. Sha et al demonstrated that inorganic materials can remain mostly stable under ultraviolet irradiation, while this condition would age the organic ones [13,23].…”

“…Cao et al verified the reduced anti-skid performance of heat-reflective road surfaces [7,17,[23][24][25][26], and reported that a controlled dosage of heat-reflective coating within 0.8 kg/m 2 can still satisfy the Technical Standards of the Chinese Technical Specifications for Construction of Highway Asphalt Pavements (JTG F40-2004) [27]. Sha et al demonstrated that inorganic materials can remain mostly stable under ultraviolet irradiation, while this condition would age the organic ones [13,23]. Cao et al also tested the permeability of heat-reflective pavements, finding that they are basically impermeable because the coating almost seals their surface, preventing water from entering the concrete interior and, hence, avoiding asphalt and pavement damage [12].…”

“…Cao et al also tested the permeability of heat-reflective pavements, finding that they are basically impermeable because the coating almost seals their surface, preventing water from entering the concrete interior and, hence, avoiding asphalt and pavement damage [12]. The microstructures of the heat-reflective coatings and their components have been investigated via scanning electron microscopy [16,18,23,26,[28][29][30][31][32]. Moreover, Hu et al performed accelerated wear tests to study the wear performance of these coatings; the results showed quality loss after wearing, but an improved anti-skid granular stirring method could enhance the wear performance [17,24,33].…”