Accurate Characterization Of Asphalt Pavement Macro Texture And Study On Attenuation Law Of Skid Resistance

The skid resistance of asphalt pavement is one of the important factors to ensure road safety.The evaluation method and evaluation index of pavement skid resistance are one of the prerequisites for comprehensive evaluation and characterization of pavement skid resistance There is no good evaluation method and evaluation index.It cannot reflect the real skid resistance the road surface,and further affect the maintenance decision of the road skid resistance.According to the research,the skid resistance of the pavement decays faster,but there are few researches on the decay speed and law of the skid resistance of the pavement.Therefore,this paper researches the attenuation law of macro texture and skid resistance of outdoor asphalt pavement and indoor simulated asphalt pavement.First of all,this paper selected 6 road projects in Beijing.With the help of a high-precision laser scanner and a dynamic friction coefficient meter,the macro-texture changes and skid resistance of the 6 roads were tracked and tested in 3 stages.With the help of SPSS software and the correlation analysis of the collected macro texture indicators and dynamic friction coefficients,it is found that any two of the macro texture indicators R_a,R_q,R_zand MPD are highly correlated,and the macro texture indicators R_a,R_q,R_z,MPD,R_ku and friction coefficient F₆₀are both moderately linearly related.The R_a,R_q,R_z,R_ku and MPD indexes are recommended to characterize the skid resistance of the road surface.With the help of Weka software,the collected macro-texture data and dynamic friction coefficient are deeply excavated,and a linear model and a non-linear model between the macro-texture index and the dynamic friction coefficient F₆₀ are established.Secondly,the collected macro texture index and dynamic friction coefficient are analyzed from the angle of asphalt mixture type and attenuation.The results show that the macro texture,skid resistance and attenuation of skid resistance of the pavement are all affected by the type of asphalt mixture.In the comparison between the AC-13type,AC-16 type and the ultra-thin wear layer,the macro texture index and skid resistance of the AC-16 type and the ultra-thin wear layer are higher than the AC-13 type.The attenuation rate of the skid resistance is AC-13category（29）AC-16 category（29）ultra-thin wear layer;in the same type of asphalt mixture,whether it is a recycled mixture also affects the skid resistance of the road surface and its attenuation speed.Recycled asphalt mixture Compared with non-regeneration,its skid resistance declines faster.Finally,based on the AC-13C Yangyan Road,the asphalt pavement is simulated indoors.According to the actual cumulative traffic volume after the opening of Yangyan Road,a long-period indoor pavement skid resistance degradation study was completed with the help of an accelerated loading instrument（MMLS3）.The results show that the macro-texture index and the time node at which the skid resistance attenuation becomes stable are not synchronized,and the time node at which the skid resistance attenuation becomes stable lags behind the macro texture index.