In order to investigate ice melting properties of road deicers with chemical types, theoretical comparison using performance index (PI) [1] and experimental analysis were carried out. In the theoretical comparison using PI, differences in melting ice performance properties were shown with chemical types and temperature ranges. Sodium chloride (NaCl) showed the best melting performance at -1.5~-3.5℃, but lower PI than other chemicals (CaCl2 and MgCl2) at lower temperature than -4.5℃. Calcium chloride (CaCl2) showed the best PI at lower than - 6.5℃, and at higher than -1.5℃, but the lowest PI at -1.5~-4.5℃. Magnesium chloride (MgCl2) showed the best performance at -3.5~-6.5℃, but the lowest PI at higher temperature than -1.5℃. PI can be regarded as a representative index for melting ice performance of liquid deicer, however, it is not enough to evaluate that of solid deicer, because the effect of heat of solution is not considered in PI. In the experimental analysis, comparison for ice melting performance between solid and liquid deicers was mainly carried out. Solid calcium chloride showed very good persistency and quick-acting property by the effect of heat of solution. Solid sodium chloride has no quick-acting property, but very good persistency at a mild temperature (-3℃), whereas ice melting performance declined greatly at severely low temperature (-11℃). Liquid sodium chloride and calcium chloride showed somewhat good quick-acting property, but inferior persistency to solid ones.
OBJECTIVES : This is a basic research for the domestic production of airport-airside deicers. This research selected basic materials for deicers appropriate for the pavement of domestic airports by evaluating the deicing performances of basic materials used in internationalstandard airport deicers and their impacts on pavements. METHODS: Laboratory investigation was conducted to evaluate the asphalt surface tensile strength, concrete scaling impact, ASR impact, and deicing performances of sodium formate (NaFm), potassium formate (KFm), sodium acetate (NaAc), and potassium acetate (KAc), which are the basic de-icing materials commonly used at international airports, approved by the FAA. In addition, the analyses were also performed on the airside deicer urea, which is currently used in domestic airports. RESULTS : Laboratory investigation confirmed that sodium formate, potassium formate, sodium acetate, and potassium acetate had superior surface tensile strength, concrete scaling impact, and deicing performance compared to airside urea, but they also had greater impacts on concrete ASR. Among these materials, sodium formate had the best asphalt surface tensile strength, concrete scaling impact, and deicing performance, while also having the greatest impact on ASR; hence, mitigation plans for ASR were needed, if it were to be used as airport-airside deicer. CONCLUSIONS : It is necessary to consider additional additives to prevent ASR of concrete pavements when developing airport-airside deicers using sodium formate, potassium formate, sodium acetate, and potassium acetate.
본 연구는 도로 상의 눈이나 얼음의 제거에 사용되는 융빙제와 부식방지제 및 저부식성 제설제 그리고 이들의 조합에 대한 성능 및 구조물에 미치는 영향에 대하여 분석하였다. 동결융해 후 무게손실률은 저부식성 제설제가 융빙제와 부식방지제 및 이들의 조합보다 적게 나타났고, 상대동탄성계수 감소는 물, 저부식성 제설제 및 NaCl+JF-1004를 제외하고 융빙제와 부식방지제 및 이들의 조합물들은 동결융해 150사이클 이후에 급격히 떨어지는 것으로 나타났다. 또한 동결융해 후 콘크리트는 물을 제외하고 상당히 심한 표면 손상을 나타냈다. 융빙 효과는 융빙제와 저부식성 제설제 및 부식방지제의 조합하여 사용할 때가 이들 개별적으로 사용될 때보다 우수한 것으로 나타났고, 저부식성 제설제 및 부식방지제의 단독 사용은 초기 융빙 성능 뿐 아니라 지속성도 현저히 낮아 현장 적용에는 문제가 있는 것으로 판단된다. 강재부식시험의 pH는 저부식성 제설제와 NaCl+JF-1004의 pH는 알칼리성을 띠는 반면에 이외의 나머지에서는 중성에서 산성으로 변화해 가고 있는 것으로 나타났고, 염화나트륨의 조합물이 다른 수용액보다 상당히 빠르게 무게감량이 나타나 강재 부식속도가 빠르게 진행되는 것으로 나타났다. 이상으로부터 도로상의 눈이나 얼음의 제거를 위하여 융빙제의 조합물을 사용 시 최대한 도로 포장 및 교량에 손상이 적게 미치는 조성물에 대한 신중한 선택하여 사용해야 할 것이다.