Chloride-based deicing material is excellent to dissolve ice and snow in economical but they accelerate deterioration of concrete or corrosion steel reinforced concrete. Chlorine ions contained in the chloride-based deicing material currently used act as catalysts for accelerating corrosion when the air-void level is above a concentration level, even if the airvoid retain the proper alkali level. Environment-friendly CMA based deicing material has been difficult to use due to high unit prices in the past, but recently prices have stabilized. As an environment-friendly deicing material agent citric acid, which is a typical organic acid in citrus fruits, plays a role of controlling pH and preventing oxidation. This is effective against reducing steel corrosion and concrete deterioration. In the long term, environment-friendly deicing material is economical considering the damages of structures due to existing chloride-based deicing material. Although environmnet-friendly deicing material has these various advantages, they are inferior in performance to existing chloride-based deicing material. This study suggests proper utilization methods through analyzing the effects of existing chloride-based and environmentfriendly deicing material. Experimental results show that some environment-friendly products a similar level of ice-melting effects of existing chloride, but the effect of chloride-based deicing material is relatively good. This suggests that the performance of ice-melting is inferior only with the use of the environment-friendly deicing material. Therefore, it is necessary to improve deicing methods using with environment-friendly deicing material such as sand and other friction material. Further, it is considered that if the frozen area is predicted in advance and spraying is possible, the environment-friendly deicing material can be used more effectively.

▪ About Heat island? In the city, there are many concrete and asphalt structures easily heated by solar heat. Also, while the fuel of factories, homes and cars in the city is burned, it generates heat at the same time. Due to these, there is the phenomenon called the heat island effect that the temperature of the city is 2 to 5 ℃ as high as of the suburb. As for widely known isolation-heat technology, there are reflection-paint coating(structure and pavement), heat-reduction pavement(water retention). Applying reflection paint to a building and pavement can reduce the surface temperature of the building up to 30 ℃, and 15 ℃ over the pavement. In summer, heat-reduction pavement(water retention) has the effect of reducing the pavement surface temperature to 10~20 ℃ ▪ Solution We can consider ways about applying heat-reduction pavement(water retention) to main section of expressway, spraying water using dirt wagon and applying reflection paint to office and tollgate.

The bond property is mightily important in asphalt construction site as overlay, post-cutting overlay and new establishment of asphalt pavement. If the bonding between the lower and upper pavements isn't approriately applied, the slipping phenomenon can happen due to the tensile stress and shear stress. It can resultantly take the forms of the rutting, failure and other damages. Moreover, the greater damage phenomenon from the intense reflection cracking can be generated when the appropriate methods regarding the cracks or failures on the lower pavement aren't conducted and the bonding with its pavements isn't properly applied. In this regard, the researched content on the existing research is shown below. The types of asphalt emulsion applied to the pavement construction site are classified as Tack-Coat and Prime-Coat in South Korea. The application purpose of Tack-Coat is to bond the pavements comprised of the rigid material. And the application objective of Prime-Coat is to attach the layers consisting the disturbed materials. The best performance related to the optimum application rates depends on the type or property of the emulsified asphalt materials. To solve these phenomenons, the various researches have been globally done. The test methods to obtain the optimum application rates of the asphalt emulsion vary in different organizations or countries. The objective of this research is to develop the tester for Tack-Coat bonding property in accordance with the standards and circumstances of the pavement construction in South Korea. In the nation, the application rate of Tack-Coat is presented as 0.3 l/m2 ~ 0.6 l/m2 in the construction specification and pavement design guideline published in the Ministry of Land, Infrastructure and Transport (MOLIT), but there aren't the specific suggestions. And, it depends on the superintendents or the ordering bodies in the construction sites. In that regard, the objectives of this paper are listed below. First, Suggestion of the test methods regarding the Interlayer Shear Strength in accordance with the domestic construction conditions and standards. Second, Development of the tester for conducting various tests using a tester. Last, Development of the predictive model for the optimum application rates of the emulsified asphalt.