The Study Of Material Properties And Structure Combination Of Cold Recycled Asphalt Pavement

The pavement cold recycled technology can effectively use waste, its conforms to thedevelopment concept of our our country sustainable development strategy of waste recycledand energy conservation and emissions reduction. At present, the asphalt pavement coldrecycled technology has not been formed a complete system,we still in the initial stage,it isdifferences from foreign in the test method, test means, design standard, pavementstructure.we study less in the structure response of recycled pavement. It is usually adoptsHMA pavement structure design method and pavement reconstruction design methods.theparameters volunme value solely rely on specification recommended, such designed pavementcan not meet the needs of the performance and the service life often shorter.Based on this, the article studyed the preserve modes and the design index of coldrecycled mixture design through the performance test and on-site validation methods, andproposes an emulsified asphalt cold recycled mixture preservation methods. And put forwardthe recycled mix design index that use the freezing and thawing and dry wet cleavage strengthand its intensity ratio as control index, and the voidage, Marshall stability as a referenceindex. According to the pavement damage type and degree, set up seven recycled pavementstructure and a kind of traditional maintenance pavement structure, through the actualpavement structure dynamic response analysis found that the temperature sensitivity ofstructure strain less than the hot mix asphalt pavement structure.the thickness of layer haslarge influence on the strain of thebottom of recycled layer; Along with the axial load andtemperature increases, recycled layer bottom tensile strain increases unceasingly, the higherthe temperature, the faster increasing of maximum strain;pavement thickness has large influence on the top surface stress of the layer under therecycled sturcture,and the speed has smaller affect According to the pavement structurestrain response,CRP3that the thickness of pavement structure is thinnest and its longitudinalstrain response is maximum, the longitudinal strain response from big to small order: CRP3(CRP4)> CRP5> CRP6> CRP1(CRP2)> CRP7, which CRP3and CRP4, CRP1and CRP2,CRP6and CRP8except cement different besides the others all the same, and be close to strainresponse function。 Based on the measured dynamic pavement response and pavement material propertiestesting, analysis was conducted on the recycling pavement structure and interlayer contactconditions. Results showed that the strength of recycling pavement layer, the thickness ofasphalt layer and the state of interface contact conditions had significant impacts on pavementperformance. Material parameters of cold recycled pavement were put forward based ontheoretical calculations and measured data analysis, which will contribute to solve theproblem of the difference between theoretical calculations results and real values. Fatiguelimit of typical recycled asphalt mix was preliminarily determined based on laboratory fatiguetesting and test road for recycled mixtures. Typical recycled pavement structure underdifferent traffic levels was recommended based on laboratory testing and measured dynamicresponses of test road.