The Research Of Reasonable Structure Of Asphalt Overlay On The Old Cement Pavement

Guangxi Zhuang Autonomous Region is one of the provinces with the largest cement pavement in China.With the economic development,the early construction of high-grade highway and the provincial highway trunk road has been a different degree of damage.Although the daily conservation and special conservation,but still can not fundamentally solve the current problems of pavement disease,the need for maintenance or upgrading of maintenance,and the cement pavement paved into asphalt pavement is the best solution.At present at home and abroad there is no uniform old cement pavement with asphalt surface structure design system and reasonable structure program.In view of this,this paper puts forward the reasonable structure of the asphalt pavement of old cement pavement by means of data research,structural calculation,experimental study and engineering application,aiming at the climate and traffic characteristics of Guangxi area and relying on the reconstruction project of Liunan Expressway.The main conclusions are as follows:(1)Guangxi Zhuang Autonomous Region is located in the hot and humid areas of South China,with high temperature,rain,air humidity and other natural environment characteristics,for the old cement pavement asphalt surface layer of the main technical needs are: to solve the high temperature climate conditions,high temperature stability of the asphalt surface,Rain conditions under the conditions of asphalt pavement water stability and surface anti-skid and other issues,for the thank you demand,put forward the corresponding technical countermeasures.(2)Based on the functionalized design method of asphalt pavement and material integrated design,the asphalt overlay structure and material of Liunan Expressway are designed according to the reconstruction project of Liunan Expressway.Based on the functional design of the system,the design concept of the stress absorption layer,the middle layer and the surface layer of the Liunan Expressway is optimized based on the performance balance design concept.(3)Cement pavement and asphalt overlay for two different nature,different strength of the pavement material,when the two between the layers of bonding materials,will form two interfaces,in order to improve the effect of interlayer bonding,the need to ensure that the two The interface has a good bonding effect.(4)The interface is humid is not conducive to the cement pavement and asphalt overlay interlayer adhesion;asphalt overlay maximum nominal particle size,the greater the depth of construction for the interlayer shear strength more favorable;adhesive material selection is the main factor : Interlaminar shear strength level,viscous material viscosity and viscosity and asphalt overlay thickness.(5)In addition to the rutting caused by material variation,construction factors and changes in traffic volume,the pavement structure of the Liunan Expressway expansion project is very effective,whether it is 12 cm pavement of the general road section or 14 cm reinforcement function Pavement layer has a good use of the function,layer thickness is more reasonable,is a relatively successful old cement pavement layer structure layer thickness program.(6)According to the characteristics of climate,transportation and highway construction in Guangxi,according to the technical and economic characteristics of different pavement materials,it is put forward that the old cement pavement of Guangxi hot and humid area is suitable for different traffic grade,different old road conditions and different user needs.Structure and combination scheme,which provides useful reference and guidance for the design of cement pavement of high grade highway in Guangxi area.Asphalt overlay structure directly affects the old road after the transformation of the service life and project cost,choose a reasonable layer of laminated materials,structural and program thickness and structural thickness of the old road reconstruction project is the key,this paper proposed the old cement pavement The rational structure of asphalt layer can not only provide the technical and economic optimal pavement structure scheme for solid engineering,but also has important guiding significance for maintenance,maintenance and decision-making.