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Effect of chelating additive on microstructure, hydration products and mechanical property of mortar under different curing conditions was investigated. The microstructure was tested by nuclear magnetic resonance and scanning electron microscope. And the chemical composition of hydration products was analyzed by X-ray diffraction. The compressive strength was measured under different curing conditions at different curing age, including standard curing, water immersion, seawater immersion and salt mist curing. After curing for 28 days in water, compared to control mortar, the reduction ratio of harmful pores whose size larger than 0.1μm in mortar with chelating additive (CA mortar) was 14.6%, followed by 8.9%, 9.2% and 2.9% which was under standard curing, seawater immersion and salt mist curing, respectively. From the scanning electron microscope image, there were more needle-like and bar-like crystals in CA mortar making it more compact, which was mainly calcium silicate hydrate through component analysis. Besides, the raising percentage of compressive strength of CA mortar under water immersion is 28.6% compared to control mortar at the age of 28 days, followed by 26.8%, 21.8% and 16.3% which was under standard curing, seawater immersion and salt mist curing, respectively. The results indicate that chelating additive can enhance compactness and compressive strength of cement-based materials especially under water immersion by promoting the formation of calcium silicate hydrate.

A silicone based self-deicing coating was prepared by blending of silicone solution and organics-coated NaCl deicing additive. The effects of deicing additive content and coating amount on freezing point of coating surface and adhesion force between ice and coating were investigated. The deicing durability of self-deicing coating was evaluated by immersion test. And the influence of silicone based self-deicing coating on friction coefficient and structure depth of asphalt pavement was researched. The experimental results showed that freezing point of coating surface and adhesion force between ice and coating decreased with the increase of the organics-coated NaCl content, freezing point and adhesion force of the self-deicing coating with 6wt.% organics-coated NaCl were-5.2°C and 24.5 N respectively. Immersion test results showed that the deicing performance had only a small reduction after immersion in water for 3 days,which indicated the self-deicing coating had good deicing durability. Moreover, silicone based self-deicing coating had slight influence on friction coefficient and structure depth of asphalt pavement due to the good permeability of silicone solution. The friction coefficient of asphalt pavement decreased by 10.4%, and the structure depth decreased by 6.1% when the amount of the self-deicing coating was 300 g/m2.