Structural Analysis Of Asphalt Pavement Of Combined Base On Finite Element Method

In our country,the design period of asphalt pavement is stipulated.But,in actual operation,it is far from reaching the design life of large and medium-sized repair,The main reason is that the design of asphalt pavement structure in our country only pays attention to the strength of the base layer and neglects the function of the surface layer,The difference between the concept of long life asphalt pavement is relatively large.Due to the current situation of our country,it is not practical to blindly copy the flexible asphalt pavement.Therefore,our country introduces and digests the concept of foreign flexible base asphalt pavement,and puts forward the structure form of combined base course,Through the application of practical engineering,it has achieved very good results.In this paper,based on practical engineering,using the finite element method to analyze the structure of composite asphalt pavement,and puts forward the index of the composite base asphalt pavement structure design,at the same time,the influencing factors of each index are analyzed.(1)Comparative analysis of China's semi-rigid base asphalt pavement and foreign long-life asphalt pavement characteristics,put forward reasonable asphalt pavement with combined base in our country,and elaborated the domestic and foreign research status of long-life and endurance asphalt pavement.(2)This paper introduces the application of composite asphalt pavement in Shaoguan Ganzhou expressway.Through the investigation and analysis of the asphalt pavement condition,it is found that the combined base asphalt pavement is in good condition.(3)this paper introduces the theoretical basis of the finite element analysis of asphalt pavement structure,including the asphalt pavement structure analysis theory and finite element theory.(4)Analyzing the mechanical response of semi-rigid base and composite base asphalt pavement under moving load using ANSYS method,including the vertical displacement,vertical dynamic stress,horizontal dynamic stress,shear stress and compressive strain.This will be of guiding significance for the design and construction of the combined base asphalt pavement.(5)In this paper,the mechanical indexes of composite asphalt pavement structure design are presented,which are the bottom tensile strain of asphalt layer,the tensile stress at the bottom of the inorganic binder layer,the compressive strain on the top surface of the subgrade,and the compressive stress on the top surface of the asphalt layer.In this paper,the possible influence factors of each index are analyzed.Through the research of this topic,the characteristics of the structure of the composite base asphalt pavement are obtained,the structural design index of the asphalt pavement is determined.and analysis of various indicators by the relevant factors.This provides some reference and guiding significance for the design,construction,maintenance and other aspects of the combined asphalt pavement in our country in the future,it has some practical value.