Research On Key Technology Of Granulated Crumb Rubber Anti-ice Asphalt Pavement

Bad traffic condition because of snow and ice in winter often cause significant casualtiesand property losses, so many methods are put forward by transportation department all overthe world to solve this problem. Granulated crumb rubber asphalt pavement is a new kind ofecological method to anti-ice. Granulated crumb rubber act as aggregates in mixture, whichare crashed from scrap tires. Ice layers are in different conditions on granulated crumb rubberasphalt pavement for elasticity of granulated crumb rubber. Thus it can be eliminated frompavement. Now the technology about this method is imperfect and defective, and there arestill many problems to be solved, such as the durability of the pavement, the elastic modulusof the pavement, and the damage mechanism of the ice etc. This research focuses on the keyproblems to do more in-depth research.(1) Micromechanical Analysis of Granulated Crumb Rubber Asphalt Mixture Based onthe Discrete Element Method. The models of discrete element method about suspended densestructure granulated crumb rubber asphalt mixture, dense framework structure granulatedcrumb rubber asphalt mixture and common asphalt mixture are established, and thecharacteristics of force and deformation under load about the three kinds of asphalt mixtureare analyzed. Based on the analysis about force and deformation of the area of granulatedcrumb rubber under load, the relationship between carrying capacity and deformation capacityand the damage mechanism of granulated crumb rubber asphalt pavement are provided, andthe corresponding improvement is given.(2) Study on Design Method and Performance of Granulated Crumb Rubber AsphaltMixture. Because the technical index of granulated crumb rubber is different from that ofaggregate, the common design method of asphalt mixture is not suitable for granulated crumbrubber asphalt mixture. This research puts forward a kind of design method aiming atgranulated crumb rubber asphalt mixture, and combined with proposed improvementmeasures for the durability, the performance of suspended dense structure and denseframework structure granulated crumb rubber asphalt mixture are analyzed.(3) Study on Evaluation and the Key Index of Durability. This research analyses thestandard test method about water stability of current specification, and combined with thedamage mechanism of granulated crumb rubber asphalt pavement based on the micromechanical analysis, the test method of durability evaluation aiming at granulatedcrumb rubber asphalt mixture is given. Compare the durability performance of granulatedcrumb rubber asphalt mixture with common asphalt mixture, the durability evaluation indexaiming at granulated crumb rubber asphalt mixture is put forward.(4) Study on the Elastic Modulus Prediction of Granulated Crumb Rubber AsphaltPavement Based on the Micromechanics Model. This research presents a kind ofmicromechanics model which can predict the elastic modulus of granulated crumb rubberasphalt mixture based on the micromechanics method and the multiple steps ofhomogenization method. Experiments are carried out and the results demonstrate that theprediction model is reliable, and the influence of properties of every ingredient on the elasticmodulus of the granulated crumb rubber asphalt is analyzed by the prediction model.(5) Study on the Anti-ice Mechanism and Effect of Granulated Crumb Rubber AsphaltPavement. The finite element model of pavement structure and ice is established, and thecalculation results show that fracture failure criterion is more suitable for evaluating thecracking of ice. Strain energy density factor criterion is introduced as the criterion basis, andpointed out that the mixed mode fracture failure is the main failure form of ice. Therelationship between elastic modulus of granulated crumb rubber asphalt mixture and theeffect of eliminating ice is analyzed when the temperature and the thickness of ice aredifferent, and the relative experiments are carried out.(6)Paving Test Road. Test road is paved in order to verify the theoretical analysis andlaboratory test results. The performance of the granulated crumb rubber asphalt pavement isobserved, and the results demonstrate that the theoretical analysis and laboratory test arereliable.