Study On Anti Sliding Performance Of GAC-13C Asphalt Mixture

anti-skid level of asphalt pavement decreases with the increase of service life,and some anti-sliding ability of the pavement is lower than the design requirement after 3 to5 years of operation.How to improve anti-sliding performance of the road surface by improving aggregate performance and grading composition is a problem that needs to be solved urgently in the engineering field.For this reason,this paper carries out relevant experimental research on the anti-sliding performance of GAC-13 C asphalt mixture.The main research work and conclusions are as follows:First of all,through analyzing and summarizing the influencing factors and testing methods of anti-sliding performance of asphalt mixture,it is considered that the gradation composition of aggregates and the performance of aggregates have a greater impact on skid resistance,aggregates,asphalt content,etc.affect the anti-sliding performance of pavements through micro-structure.Mixture types and gradation influence the anti-sliding performance of the road surface through macroscopic structures.At the same time,the pendulum friction coefficient measuring instrument method and the manual sanding method are more in line with the actual indoor test methods to study the anti-sliding performance of the mixture.Secondly,the GAC-13 C asphalt mixture was gradated and the pass rate of 4.75 mm mesh was changed by ±3% and ±6% to obtain four additional gradations.Using the density method and the CAVF volume method to test the skeletal compactness of the five gradations,it was found that the selected gradation 1,2 skeleton structure is poor,and the gradation 3,4,and 5 are almost skeleton dense structures.Then,based on the analysis of the influence of the anti-sliding performance of the class pairing based on the fractal theory,the analysis of the correlation between the4.75 mm mesh pass rate and the fractal dimension D yields that D1 can better simulate the fractal dimension and the mesh pass rate,ie the gradation Relationship between.Therefore,by using D1 as the fractal parameter to study the effect of the graded Marshall parameter and road performance,it is concluded that D1 gradually increases,the mixture becomes coarser,the saturation and residual stability decrease,and the material gap rate,dynamic stability,and pendulum The value and construction depth gradually become larger.Reduce the pass rate of 4.75 mm mesh,the coarse aggregate of the mixture forms the framework embedded structure,improve the high temperaturecapability and anti-sliding ability of the mixture,and at the same time,design the target voidage with 4%~5%,there is enough fine aggregate Filling the gap sufficiently,although the water stability is relatively reduced with the increase of D1,the dense water structure formed by the mixture makes the mixture have good water stability.Thirdly,the change law of the anti-sliding performance of GAC-13 C mixture is changed by ±0.2% on the basis of the mixture's whetstone ratio.The fractal surface model is used to calculate the specific surface area based on the subdivision of the void fraction,and the specific surface area calculated by the current specification is compared with it.Show that using its calculation of the oil film thickness can reflect the actual oil film thickness of the mixture.At the same time,the oil film thickness and anti-slip index are analyzed.The results show that the anti-sliding value of the mixture increases first and then decreases with the amount of asphalt.When the oil film thickness is too thin,the anti-sliding performance is good and its stability is poor.The more coarsely matched skid resistance is more sensitive to the amount of asphalt.Afterwards,the anti-sliding performance of the gradations of the two groups of A and B with different angularities was comparatively analyzed.The results showed that the coarse aggregate angularity and the fine aggregate angularity all had some influence on the anti-sliding performance of the mixture.The greater the sex,the greater the anti-slip performance.At the same time,coarse aggregate angularity has a greater effect on anti-slip performance than fine aggregates.In addition,for the graded GAC-13C-3 to GAC-13C-5,the coarser the gradation,the greater the amount of change in the angularity of the coarse aggregate,the more sensitive the angularity to anti-slip performance.Finally,the three-wheel accelerated loading test was used to investigate the anti-sliding degradation of GAC-13 C asphalt mixture.It was found that after 320,000 rounds of wheel load,the wheel trace depth was more obvious.At this time,the oscillating value of the three gradation mixtures tended to It is stable,and the pendulum value decays logarithmically.The final stable pendulum values are 53 for GAC-13C-3,56 for GAC-13C-4,and 60 for GAC-13C-5.The GAC-13 C mixture has better stability.The anti-sliding durability.The other grade GAC-13C-5 is more nearly skeleton dense structure,its initial value of the pendulum value,attenuation amplitude and final value are greater than the other two gradations,the gradation composition,stability and the strength of the skeleton structure are all on the mixture.Anti-slip performance has a certain influence.