Application Of MS-4 Micro-surfacing In Preventive Maintenance Of Highway In Gobi Area Of Gansu Province

In recent years,with the rapid development of the national economy,China's highway construction has made breakthrough progress.Affected by climate,geography,traffic conditions and other factors,the highway has good conditions,but there are some early diseases.Micro surfacing is a quick and effective preventive maintenance measure to save investment.By analyzing and summarizing the application of micro surfacing in Gansu Province in recent years,the design and construction plan of micro table suitable for our province is screened out.Based on the analysis of the composition and influencing factors of emulsified modified asphalt,the design of micro surfacing mixture ratio,the influence factors of 1H wet wheel wear value and its road performance,the following conclusions are drawn.Soap solution pH value only in pH reached to play the biggest role when a certain value,in order to have the best solubility,2.2-2.5 is the best;adding storage stability to increase the yield of modified asphalt emulsion stabilizer,but the ductility decreases,the optimum adding amount was 0.1% Sika;and MeadWestvaco two have a good effect of emulsifier emulsion for SK90 asphalt,the optimum content is 1.8% ~ 2% and 1.2% ~ 1.4%;and domestic PC-1468 modifier produced by SBR modified asphalt,evaporation residue index and high temperature properties of low temperature performance are greatly improved,the optimum adding amount was 3% and from 2.5% to 3%.In wet wheel wear test,with the increase of emulsion dosage(asphalt to stone ratio)and modifier dosage,the wet wheel abrasion value of micro surfacing mixture decreased obviously.The mixture ratio design of MS-4 type micro surfacing mixture,the optimum whetstone ratio is 6.7%,and the cohesive force of 60 min is 2.1N = m.The test shows that the MS-4 type micro gauge 1H can open the traffic.And with the MS-3 type micro surfacing were obtained: MS-4 type micro surfacing with anti rutting ability is very good,suitable for the treatment of severe rutting depth larger pavement;MS-4 type micro surfacing late strength and abrasion resistance than MS-3 type.