Asphalt Mixture Segregation Control And Pavement Compaction Technology

Based on the research at home and abroad,this paper analyzes the investigation of asphalt pavement segregation,and proposes the prevention and control measures of asphalt pavement segregation from the aspects of materials,equipment and technology.The highway is analyzed by sanding method,nuclear density meter method and infrared camera method.The research shows that there are many types and degrees of segregation in the construction of highway asphalt pavement.Combined with the construction technology level of Tianjin,and a lot of investigations on highway construction,the criteria for determining the segregation of asphalt pavement were put forward.Through the investigation of domestic and foreign research results,the reasons of road surface segregation were studied,and the technical measures to prevent road surface segregation were put forward from three aspects: mechanical equipment,construction technology and raw materials.This paper analyzes the types,characteristics and rolling procedures of asphalt pavement compaction equipment.The effects of material properties,interlayer thickness,asphalt mixture temperature and climate on compaction were analyzed.The compaction equipment commonly used in asphalt pavement construction in Tianjin was investigated,and its technical parameters were analyzed.The asphalt pavement compaction equipment was proposed.Configuration requirements.According to the type of asphalt mixture commonly used in Tianjin,the corresponding rolling construction technology and void ratio determination standard are proposed.On the basis of a large number of field tests,the correlation between the void ratio and the water permeability coefficient was analyzed.It is suggested that the control index of AC-13,AC-20 and AC-25 water permeability coefficient is 45ml/min.Studies have shown that different mixtures should have different compaction requirements;the water permeability coefficient has a significant positive correlation with the structural depth;that is,the water permeability coefficient increases with the increase of the structural depth;but the water permeability coefficient and the asphalt layer thickness There is a slight negative correlation,that is,the water permeability coefficient decreases slightly as the thickness between layers increases.The seepage coefficient of asphalt pavement is unevenly distributed in the cross section of the pavement.The seepage coefficient of the overpass is the largest,and the seepage coefficient near the middle zone is large.The compaction of the pavement near the middle zone should be strengthened.This paper has formulated the technical requirements for raw materials,mix design,mix and construction in asphalt pavement construction control.The guidance of highway asphalt pavement construction has been formulated and has been applied to the expressways construction.At the same time,the method of dynamic control of construction quality is carried out by (?)-s graphs and (?)-R diagrams,which has high engineering practice value for improving construction quality control level.