Simulation Study On Anti-skid Performance Based On Tire-road Contact Characteristics

With the continuous development of high-grade highway construction,the construction of super highway and intelligent highway has become a trend,which puts forward higher requirements for driving safety and pavement skid resistance.However,due to the complexity of anti-skid mechanism and influencing factors,indoor anti-skid performance evaluation test is too simple and rough(sand laying method,etc.),or complex equipment,time-consuming and laborious process(large-scale accelerated loading test)is difficult to be widely used,which leads to the lack of reasonable anti-skid performance evaluation and prediction methods in the design stage of asphalt mixture.Therefore,it is urgent to further improve the evaluation method of pavement skid resistance.The core of pavement anti sliding performance lies in the complex contact mechanical characteristics under multi-scale between tire rubber material and pavement texture,including the friction characteristics between tire and stone surface micro texture structure,the deformation and bite contact characteristics with macro-scale main aggregate particles and their structures,and the adhesion and contact characteristics with micro-scale asphalt mortar.From the point of view of the durability of anti sliding performance,the attenuation process of anti sliding performance is the same as that of the former and the latter,and the occlusal contact is essential in the process of anti sliding attenuation.In this paper,the simulation test and pressure film technology are used to measure and analyze the tire surface contact stress field,and a new anti sliding performance evaluation method is proposed with the contact bite force as the key analysis object.First of all,the real road texture point cloud data of the rutting board is obtained by using the self-developed road laser contour detector,which is used for data processing and denoising.The point cloud data is curved by using reverse engineering tools and used in the finite element simulation to analyze the contact surface product and stress response of the tire road under the load.The results show that the different road texture structure has a great impact on the tire surface contact Area and stress concentration state.Secondly,pressure film technology is used to further analyze the form of tire surface contact stress field,design and simplify the road stress load test,use pressure film equipment to quantify the stress value on the contact surface,summarize the data after the analysis and summarize the different size of the road aggregate particles in the tyre road surface occlusive state,the data shows that the larger the aggregate particles,the better the occlusive effect On this basis,the following simplified road simulation model is established.Thirdly,summarize and analyze the existing friction contact mechanical model,select the theory which is helpful to assist the analysis of tire surface contact anti-skid effect,extend and transform the new simplified anti-skid mechanical model,and propose the evaluation index of anti-skid performance of pavement based on the occlusal contact and anti-skid distraction,which is used to predict and analyze the anti-skid performance of mixture in the material design stage.Under the guidance of the mechanical model,based on the real road surface laser scanning data,the simplified road surface model under different wearing time is established to carry out the simulation test of the skid resistance performance of the road surface,so as to carry out the durability analysis of the skid resistance performance of the road surface,and the correlation analysis with the real indoor skid resistance test data verifies the rationality of the evaluation index.Finally,the proposed mechanical anti-skid evaluation index is used to analyze the influencing factors of anti-skid performance.Based on the tire surface contact,the influence of mixture gradation,braking speed,load,tire rubber hardness and other influencing factors on the anti-skid performance of the pavement is analyzed.The applicable scope of the proposed evaluation index is expanded and the influence degree of each influencing factor on the antiskid performance is analyzed.The test data show that the grading type with rich texture,high degree of tread contact engagement and better anti sliding performance,braking speed,load and tire hardness also affect the tread contact engagement state and anti sliding performance,and analyze the impact of their anti sliding performance respectively.Thus,a set of simulation test method based on the contact occlusion of tire and road surface is preliminarily established to evaluate the skid resistance of road surface.