Calculation And Analysis Of Long-life Asphalt Pavement Structure

With the continuing development of the national economy,traffic volume and load grow rapidly.Asphalt pavement early damage is becoming more and more serious day by day.To solve this problem,pavement researchers present a new concept "long-life asphalt pavement". It is a new researching in the field of internantional civil engineering.This paper references long-life asphalt pavement's definitions domestic and foreign. According to elastic multi-layer system theory,the author calculates and analyses the long-life asphalt pavement using Bisar 3.0.The design criteria of long-life asphalt pavement are tensile strain at the bottom of asphalt pavementε_t and compressive strain on top of the road formationε_c.First,this study arranges pavement structure combination based on orthogonal experiment method to analyse sensitivity of pavement structure factors.The principal degree of each factor has been decided,so that it offers important foundation for adjusting pavement structure design.Second,the author analyses deforming characteristic of each asphalt pavement layer.For some pavement structures,through changing each pavement structure layer factor,the author has analysed the strain's changing law of asphalt layer and maximum shearing stress changing tendency with pavement structure depth.At the same time,the strain of asphalt intermediate layer and the strain of asphalt base layer also have been compared. Then the author calculates the stress condition of graded crushed stone,compares with the perfect state and determines the factor of graded crushed stone being compressed completely. The paper also has demonstrated importance of road formation in pavement structure design. At last,the author recommends for long-life asphalt pavement structure according to the analysis mentioned above.Trial pavement section has been paved on Shaanxi-Neimenggu expressway to support the following research.