Study On Asphalt Pavement Of Lean Concrete Base In High - Grade Highway

Asphalt pavement with lean concrete base contains advantages of both asphaltconcrete and cement concrete for its combined feathers of rigidity and flexibility as well ashigh bearing capacity, which can be fairly suitable for developing trend of heavy traffic,therefore it is widely applied in highway pavement structure. For developing andpromoting fresh pavement form, it is great reality significance and application prospect tocarry out research on asphalt pavement structure with lean concrete base. Therefore, thispaper mainly focus on asphalt pavement with lean concrete base of high-grade highways.Firstly, mechanical properties of base materials from lean concrete are analyzedthoroughly. Through analysis on the major destruction forms of asphalt pavement of leanconcrete base, eight mechanics indexes are obtained, namely tensile stress and tensilestrain at the bottom of the asphalt layer, tensile stress at the bottom of the base layer,tensile stress at the bottom of the subbase layer, deflection on the surface of pavement,shearing stress and shearing strain of the asphalt layer, and vertical compressive strain onthe top of roadbed. Meanwhile, the most adverse position of each mechanics index alongpavement depth are obtained uniform distribution.Secondly, twelve factors including modulus and thickness of surface layers and base,thickness of the subbase, modulus of the roadbed and axle load are selected and furtheranalyzed through orthogonality analysis method, with the results of ordered influencedegree for each factor on the mechanics indexes.Thirdly, modulus and thickness of the lean concrete base and asphalt layer, thicknessof the cement stabilized crushed stone subbase and the axle load are concretely researched,with acquisition of influence regularity for each mechanics indexes. According to researchresults from defects of asphalt cement composite pavement, it’s definitely necessary to setthe anti-cracking interlay for improvement. The influence regularity of anti-crackinginterlay on structural stress for asphalt pavement of lean concrete was analysed byABAQUS, providing an important basis for structure designing.Finally, the reasonable structure of asphalt cement composite pavement of high-grade highways are concluded through comprehensive analysis and research, and therequirements of structure under30%and50%overload are researched.Specificrequirements of materials lean concrete are summarized;and the construction andmaterial production of rubber-asphalt anti-cracking interlay are summarized.