Study On Applying Surface Segregation As Quality Acceptance Indicator Of Asphalt Pavement

As for new asphalt pavement, related investigations revealed local pavement damage occured at random initially which often turned out extensive damage finally .These damage in the early stage of asphalt pavement is similar with the distribution of surface segregation in asphalt concrete pavement,so that it is related between the early damage of asphalt pavement and asphalt segregation.In recent years,many research organizations at home and aboard have explored extensively research on how to control the segregation during the construction. But on the whole, these researchs are belong to qualitative research. It is lack of quantitative assessment of control effectiveness , especially the research on surface segregation as indicators of quality assessment is still very lacking.In this paper,the objective is to make the surface segregation to become the quality criterion of asphalt pavement during the construction, including the segregation of the quantitative identification and the influence of pavement life.First ,analyzing the concept of asphalt mixture segregation and the reasons of the aggregate segregation and the temperature segregation in the asphalt mixture, identification of appropriate indicators for segregation are summarized, recommended structure depth and density as identification of appropriate indicators for segregation.The classification of segregation level due to the effect of aggregate segregation brings to the quality of the pavement was researched, proposed the classification level of gradational segregation.Based on this classification,it is concluded the different levels of quantitative segregation criteria.It introduced that what is standardized acceptance testing of characteristic indicator and how to determine the target value,and established a formula for calculating the rate of surface segregation. Secondly, the prediction results and applicability are discussed of sigmiod model,multinomial model,exponential model and Markov probability medel with real pavement data, recommended equation of sigmiod model as the type of predict model. It define the basic requirements for performance predic indicator which meet our need,then, determining performance predict indicator. Relying on a highway project, it establish prediction model of pavement life under different rate of segregation by the data which is the rate of construct segregation and PCI from interval segment.It establish the formula of the adjustment of payment based on life cycle cost,and determines the quality acceptance limits of AQL and RQL ,and draw the OC payment curve based on the rate of segregation.Finally, relying on a program example,it is demonstrated how to evaluate and control the nonuniform appearance during the construction by the segregation criteria in this paper,and it also puts forwoad the solutions for real problem.