Preparation Of Photocatalyst Permeable Asphalt Pavement Material With Exhaust Gas Purification Function And Its Road Performance

With the rapid development of China's economy and industry,cars have gradually become an essential means of transportation in life,bringing convenience to people,and its use has spread to cities across the country,which will inevitably lead to a sharp increase in automobile exhaust.The harmful effects of automobile exhaust on the social environment mainly include greenhouse effect,acid rain,haze weather,etc.and directly lead to factors such as respiratory diseases and some carcinogenic pollutants.Automobile exhaust brings challenging environmental pollution and personal health problems to human beings.It is not enough to maintain ecological balance by natural ecosystems.These problems have also attracted the attention of many experts and environmental protection bureaus.In view of the problems caused by automobile exhaust,domestic and foreign scholars have done a lot of research on the degradation of automobile exhaust,mainly in the screening of photocatalyst types,synthetic coatings prepared by nano-photocatalysts and binders and additives,and nano-TiO₂ light.A lot of research work has been carried out on the road performance after the catalyst penetrates into the asphalt pavement,and the influence results are discussed by using the automobile exhaust gas analyzer.However,after the nano-TiO₂ photocatalyst material is coated on the surface of the permeable asphalt mixture,there is no in-depth study on the degradation of automobile exhaust,and there are few studies on road performance and durability.The silicon-acrylic emulsion is incorporated into a photocatalytic material capable of degrading automobile exhaust gas.Because the silicone-acrylic emulsion has strong cohesiveness,the nano-TiO₂ photocatalyst material can be coated on the road by a strong viscosity to generate more exhaust gas.Because of the many hazards caused by automobile exhaust,nano-TiO₂ photocatalyst materials can degrade car exhaust and reduce personal injury.Therefore,it is necessary to carry out this research.In view of the above problems,this paper studies the preparation of permeable asphalt mixture and coating nano-TiO₂ photocatalyst material on the surface of asphalt mixture.?1?The optimum ratio and optimum coating amount of nano-TiO₂ photocatalyst were determined.Firstly,the matrix asphalt test piece is prepared by using the eight-shaped test mold,the 150-square high-quality mold,and the softening point test piece ring.The three basic performance indexes?needle penetration,ductility and softening point?of the asphalt satisfy the asphalt needle.Intrusion test specification,asphalt ductility test specification,asphalt softening point test specification;secondly,by degrading the degradation efficiency and degrading optimal time of automobile exhaust,the optimal ratio and optimal coating amount of nano-TiO₂ photocatalyst are summarized.?2?Verify the road performance of nano-TiO₂ photocatalyst materials.Compared with the water-permeable asphalt mixture coated with nano-TiO₂ photocatalyst material,the water-permeable asphalt mixture not coated with nano-TiO₂photocatalyst material is compared with the water-permeable asphalt mixture coated with nano-TiO₂ photocatalyst material,and its anti-slip performance is achieved by water immersion Marshall stability test,freeze-thaw split test and automatic rutting test.,permeability,anti-blocking performance,mechanical properties and water stability are all satisfied with road code requirements.?3?A simulated rainfall wash test and a tire crush test were designed.Explore the performance durability of nano-TiO₂ photocatalyst materials.Before and after the rain wash test,the tail gas degradation test was carried out on the same test piece to investigate the change before and after the degradation efficiency;the automatic rutting test was carried out to simulate the rolling of the tire on the road surface,and the digital camera was used to collect the picture,and the picture was grayscale processed to study the nanometer.The flaking ratio of the TiO₂ photocatalyst material.Combined with rainwater scouring test and tire rolling test,the results show that nano-TiO₂ photocatalyst material has good performance durability,and can be used for long-term photocatalysis after coating with asphalt mixture pavement.?4?The efficacy durability and high efficiency of nano-TiO₂ photocatalyst materials are revealed.The microstructure mechanism of photocatalyst materials was investigated by scanning electron microscopy and Fourier transform infrared spectroscopy.The dry silicon-acrylic emulsion and the silicon-acrylic emulsion containing nano-TiO₂ were prepared by drying oven,and the infrared spectrum analysis was carried out to verify that the silicone-acrylic emulsion played the role of bonding,and its chemical properties were not affected;The nano TiO₂ photocatalyst material containing the dispersant and no dispersant was analyzed.It was found that the dispersibility of the nano-TiO₂ photocatalyst material added with the dispersant was more uniform,and the nano-TiO₂ photocatalyst material without the dispersant appeared in a cohesive state.