Research On Construction Technology Of High Grade Asphalt Pavement With Low Carbon And Thin Layer

At present,the total mileage of China's highway has reached more than 4.57 million kilometers,ranking first in the world,of which the total mileage of the expressway reaches120 thousand kilometers.The maintenance of high grade pavement is particularly important,and energy conservation and environmental protection is the trend of maintenance work in the future.In this trend,the pavement “low-carbon and thin paving integration”maintenance mode of "spreading in layers and integrated compaction" is put forward.This model embodies the concept of road maintenance for energy saving and emission reduction,which can not only improves the maintenance level,prolongs the maintenance cycle,saves raw materials,and reduces maintenance costs,but also has great economic and social benefits.First of all,through the field survey and analysis of road disease,it is found that the early diseases of asphalt pavement mainly include cracks,rutting and poor smoothness and so on.Combined with common maintenance technology,the "low-carbon and thin layer and overlaying integration integration" maintenance scheme is proposed by contrast analysis.Secondly,through the use of ANSYS finite element method to simulate the temperature field of the pavement when use the hot in-place recycling technology,combined with the actual environment simulation obtained by the pavement heating temperature field variation,the heating time,temperature and thickness of the old pavement are determined.Thirdly,based on the analysis of RAP materials,according to the "deviation degree theory",the aggregate gradation is optimized;Using the theory of composite materials,the viscosity of regenerant was analyzed to determine the type and amount of regenerant;According to viscoelastic theory,the Maxwell constitutive model is used to simulate the deformation and stress of the integrated pavement by using the ANSYS software,the thickness-deformation,thickness-stress relationship model was established and the optimum thickness of overlay was determined.Fourthly,through the construction preparation,construction technology,quality inspection analysis,the construction process of "spreading in layers and integrated compaction" is adopted in the integrated pavement;The key technologies,such as heatingtime,rolling times,paving temperature,and quality assurance measures and evaluation methods are put forward.Finally,through the comparative analysis of the three construction technologies of the integrated pavement,the SMA-10 thin pavement and the hot recycling pavement,the results of the integration technology to meet the requirements of the standard are obtained.The integrated technology of low temperature performance and water stability has been greatly improved than the other two types of technology.And by comparing the economic benefits of integrated technology and hot in-place recycling technology,the results of low construction cost of integrated technology,effective utilization of pavement material and reducing environmental pollution are obtained.This technology embodies the concept of road maintenance for energy saving and emission reduction in China.