Research On Anti-icing Synergistic Mechanism And Performance Optimization Of Super-hydrophobic Cement Concrete Pavement

Cement concrete pavement occupies an important position in the highway.In cold weather,the snow and ice of the pavement seriously affect the safety of driving.The conventional methods of deicing and snow melting have some effect but the efficiency is not obvious in general,even some methods(such as snow melting agent method,etc.)damage to the road,pollute the environment and destruct the ecological condition.Further research on anti-icing performance optimization was carried out based on the preparation of super-hydrophobic cement concrete pavement materials.The anti-icing performance and long-term performance of cement concrete pavement were improved.Through the anti-icing test,water resistance test,sulfate corrosion test,freeze-thaw test and road performance test,the synergistic effect of SCC performance was studied.The synergistic mechanism was analyzed by microscopic test.The main research results were as follows:(1)According to the hydrophobic and anti-icing mechanism of super-hydrophobic materials,the doped and coated super-hydrophobic materials were prepared for concrete pavement.SCC pavement performance was optimized by the synergistic effect of internal mixing and external coating.The hydrophobic and anti-icing performance of the optimized SCC pavement was studied by the self-designed simulated rainfall-icing test and the icing-road adhesion test.The ice-road adhesion was measured and the relationship of adhesion strength among the different groups was obtained that the ordinary concrete group>the super hydrophobic material group>the coated hydrophobic material group>the optimization group.The micro structure of the optimized SCC specimen was observed by scanning electron microscope(SEM,which showed that the micro-nano rough structure formed by super-hydrophobic materials was one of the important reasons for its hydrophobic,anti-icing and ice reduction.(2)The results of the mechanical strength test indicated that the method of coating hydrophobic materials had little effect on the compressive strength of concrete,although flexural strength had increased,it was not obvious after 28d.The strength of concrete decreased slightly,which could still reach more than 95%of the strength of ordinary specimens doped super-hydrophobic materials.The water absorption rate of the optimized SCC was only 0.19%,which reached only 8.4%of the ordinary concrete after 36h.The sulfate corrosion test showed that,the coefficient of corrosion resistance of the optimized SCC specimens on the 150d was highest,which was 1.46 times of the control group specimens.Compared to the coated group,the corrosion resistance of the doped group was better.The freezing and thawing test showed that the quality loss percentage of the optimized SCC group after 150 freeze-thaw cycles was only 33%of the ordinary sample.The compressive strength loss percentage was only 36%compared to that of general group.(3)Field tests were carried out and the skid resistance,wear resistance and economic benefit were analyzed.The results indicated that the anti sliding performance of the optimized SCC pavement could meet the requirements of the standard,and its abrasion resistance was good and the long-term economic benefit was considerable.