Research On Skid Resistant Coat Of Cement Concrete Pavement Based On Response Surface Methodology

For years of efforts in the road industry,the problem of bearing capacity of pavement structure in China has been basically solved.In hot and humid areas,surface functional problems such as insufficient skid resistance and rapid attenuation of skid resistance are becoming new challenges in the road industry,especially in tunnels.In addition,China is the world’s largest cement production country,cement production is more than half of the world for many years.Therefore,it is of great value to apply cement-based materials in the field of skid resistant coat.In order to overcome the defects of traditional cement-based materials and promote the development of cement-based skid resistant pavement.In this paper,a new cement-based skid resistant coat material was developed based on the response surface optimization design method.The modified cement mortar was used as the coat,and on this basis,the coat surface was treated to improve anti-skid resistance.First of all,according to the elastic deformation of automobile tires on the cement concrete pavement,this paper analyzed from the perspective of energy dissipation that the anti-skid friction force of the cement concrete pavement depended on the surface gradient of the pavement surface,and was affected by the road surface,vehicles,materials,and environmental factors.On this basis,the requirements of cement concrete pavement anti-skid coat adhesion,crack resistance,wear resistance,and anti-skid performance are put forward.The study compared the effects of 8%,10%,12%,14%of waterborne epoxy resin,SBR latex,and CRL latex on the adhesion performance,and found that 14%of the waterborne epoxy resin had the most significance on improving the pull-out strength.The study compared the influence of0.4%,0.8%,1.2%,1.6%of PVA fiber,GF fiber,and BF fiber on the crack resistance,and found that PVA fiber had the most significant inhibition on the cracking index.The study compared the 8%,10%,12%,14%of SBR latex,and CRL latex on the wear resistance,and found that SBR latex had more significance on reducing wear value.Secondly,on the basis of a single factor,the response surface methodology was used to optimize the pull-out strength,cracking index,and wear value.When waterborne epoxy resin,PVA fiber,and SBR latex were mixed into the benchmark mortar at the same time,it was found that:in terms of bonding performance,waterborne epoxy resin and SBR latex showed significant interaction;in terms of anti-cracking performance,waterborne epoxy resin,there was no significant interaction between PVA fiber and SBR latex;in terms of wear resistance,there was a significant interaction between waterborne epoxy resin and PVA fiber,waterborne epoxy resin and SBR latex.Finally,the optimized conditions were determined as follows:the content of waterborne epoxy resin was 8%,the content of PVA fiber was 1.1%,and the content of SBR latex was 13.7%.The optimized results were:the pull-out strength was 0.70 MPa,the cracking index was 0 mm,and the abrasion value was 21.71 g·m^-2.Finally,the response surface methodology was used to comprehensively evaluate the structural depth,pendulum value and spalling rate of mortar.The particle size of corundum was12～24 mesh,the distribution of corundum was 4.7 kg·m^-2,and the coating mortar was 3.45kg·m^-2.The initial structural depth of the optimized skid resistant coat was 1.68 mm and the swing value was 87.2.After 70000 loaded,it still had good anti-skid performance.