Study On Skid Resistance Evaluation Of Asphalt Mixture Based On Limestone

With the rapid development of the transport industry, road safety problems havebecome increasingly prominent. Studies have shown that lack of pavement skidresistance is one of the important factors of road traffic accidents. It can effectivelyimprove the road pavement skid resistance to set anti-skidding surface. But the uniformstandards are not supplied to structure form, aggregate selection, evaluation indexes, testequipment, etc. of anti-slide surface. Then many problems still required further researchin this field.First of all, on the basis of summarizing relevant information about anti-skiddingsurface at home and abroad, the formation mechanism and influencing factors of asphaltpavement skid resistance are analyzed. An accelerated polishing test device is fabricatedthat attempts to use the way of sliding friction produced by rubber plate and asphaltspecimen to increase friction area and simulats pavement polished effect as much aspossible while increasing testing efficiency. Expected performance objectives, technicalparameters, working principle, structural features and operation method are described inthis paper.Secondly, focus on the subject of limestone, main technical indicators of aggregateare tested. The impact of aggregate properties on anti-slide abrasion of asphalt mixtureis analyzed using expert investigation method.Then the anti-slide abrasion compositeindicator is calculated. The results show that the sequence of aggregate indicatorscontribute to anti-slide abrasion of asphalt mixture is polished value>abrasion value>crushing value>solmdness>density>water absorption. The comparison of anti-slideabrasion of three aggregates, basalt is the best, followed by limestone A, limestone Bworse.Then the existing evaluation system of skid resistance of asphalt mixture issummarized in this paper. The skid resistance tests of AC-13asphalt mixture areconducted by accelerated polishing test device. The BPN and TD of specimens aretested to evaluate the skid resistance of asphalt mixture with different stones andgradations. The results evidence that the skid resistance of basalt asphalt mixture isbetter than limestone’s. And the physical and mechanical properties of aggregates withsame lithology are better, the skid resistance of asphalt mixtures is better. Coarsegradation is helpful to improve pavement skid resistance of pavement. Using the equation Y=aebX+c to regress can obtain good fitting effect. A good correlation is existin accelerated test data and other indoor anti-slide test.Through research of existingpavement friction coefficient measurement data, the correlation between acceleratedpolishing test and pavement performance is assessed and the gray prediction modelGM(1,N) of pavement skid resistance is established, to achieve prediction andevaluation of the actual pavement skid resistance at different period by the indooraccelerated polishing test.Finally, the benefit analysis of limestone that applied to anti-slide surface ofYunnan Longrui Expressway is made. The results showed that application of limestonewill not only receive good social and environmental benefits, and saving of about25.175million yuan on total project cost,157000yuan per kilometre on average ineconomic benefits.