Optimum Research On Asphalt Pavement Layer Structure And Material Based On The Operational Performance

With the constant development of transportation in our country, the service performance of asphalt pavement gets more and more attentions from highway engineers. However during the use of process, there are many diseases like fatigue cracking, rutting, subsidence, flatness inadequate may emerge before the service life, which seriously impact on the performance of the asphalt pavement. So how to reinforce service performance and extend service life of asphalt pavement has become an important issue for construction unit. In this context, carrying out the research of optimization of structures and material for asphalt pavement surface based on service performance becomes significant.Therefore in order to reasonably modify the material of asphalt pavement surface, combine the surface structure, improve the design method and enhance the service performance of asphalt pavement, the main research contents in this paper, according to the damage of asphalt pavement performance in early phase, include:(1)The situation of structures and material of asphalt pavement surface on all kinds of roads in Shaanxi Province are investigated systematically in this article, which lead to the composition characteristic of all kinds of roads. (2) This text relies on "Yanwu secondary road", the mechanical behavior of pavement structure for typical secondary roads is analyzed systematically; The region of fatigue resistance,track resistance and Low temperature shrinkage resistance on asphalt surface are determined respectively; Horizon function and reasonable thickness of each surface course are put forward. (3)The pavement performance of modified asphalt mixture which is commonly used by different surface and bottom layers of pavement is analyzed through the systematic laboratory experiments. Based on interval approximation method, rational modification method of asphalt mixture is put forward for first time. Mix Proportion Design method and reasonable essential ingredients of bottom layers of asphalt pavement are proposed.(4) The improved fatigue simulation experiment of base and surface course for asphalt pavement, based on the Wheel Tester, is put forward for the first time. The fatigue simulation experiment of different loads and different combinations of materials and structures is conducted. The influences, which are resulted from different factors, on fatigue crack reflection of surface course for asphalt pavement are drew. The typical structure for secondary asphalt pavement which is based on the service performance is introduced. With the life cycle cost analysis, the engineering economy between the introduced and the original pavement structure is compared and analyzed. (5) By contrast the current asphalt pavement design control index between domestic and overseas, Design control index and standard of design integration for pavement structure and material are put forward. With the index included rutting, low temperature shrinkage and fatigue, the method that research and analyze the horizon function of each structure layers for asphalt pavement is put forward, the axle load conversion method corresponding with the indexes is determined. Horizon function of each asphalt structure layers is analyzed, which lead to the composition demand of asphalt mixture. The design process of design integration is proposed in this paper combined with traditional asphalt pavement design method of our country.