The Structure Analysis And Performance Research On Composite Pavement With Anti-cracking Interlayer

Compared with the traditional rigid pavement and flexible pavement,AC+PCC rigid-flexible composite pavement structure combine the advantages of both,which not only in carrying sufficient traffic load but also providing good driving conditions.But this rigid flexible composite pavement structure is inclined to produce crack reflection,which put greatly limits of the popularization and application of this new type of pavement structure.Through theoretical analysis,this article carries on a research the structural performance of composite pavement reinforcing,and anti cracking of sandwich,to probe the anti cracking mechanism of reinforced materials,and evaluate c its anti effectiveness comprehensively.In this paper,I take the use of finite element software ABAQUS to establish the imposition of a three-dimensional finite element model of anti cracking reinforced sandwich composite pavement structure,choose AC+PCC rigid flexible composite pavement structure AC bottom layers of maximum tensile stress,maximum shear force and the PCC board top,the maximum bending sink the worst as the mechanical analysis indicators,to study the effects that impose reinforcing,and anti cracking layer of steel wire net of rigid will take to flexible AC+PCC composite type pavement structure of reflection crack prevention.We choose galvanized wire mesh as imposing band anti cracking interlayer materials,combining with China's current highway asphalt pavement design specification,to analyze steel wire and wire mesh,wire mesh implantation layer structure according to the position of the AC layer should stress state and galvanized steel wire mesh interlayer in the modulus of the base,changes in the size of the load state of AC layer stress of main influencing rules of galvanized steel wire mesh interlayer of composite pavement structure of rigid and flexible new AC+PCC cracking mechanism.Through the analysis of the obtained 1)steel wire mesh interlayer are closer to the composite pavement asphalt rigid AC+PCC at the bottom layer can effectively prevent reflection crack Under the condition of overload is not recommended;2)in the initial stage,increase the subgrade modulus can to a large extent improve pavement structure layer of load stress,but when the subgrade modulus exceeds a certain range,continue to improve the subgrade modulus unrewarding will get little impact;3)although the base modulus increase to a certain extent to reduce the structural layer stress effect,but this effect is still not too obvious,taking the economic effect into consideration by increasing the base modulus to reduce pavement load stress;4)in wire mesh by its high tensile strength and low elongation rate to achieve remission of joint of stress concentration and vertical shear displacement,thus effectively inhibited the cross To the open type,horizontal shear type and vertical shear reflection crack generation and expansion,enhance the use and stability of pavement structure,and prolong the service life of the pavement structure.Through the establishment of composite pavement structure three-dimensional finite element model for the analysis of the temperature load structure,and studies the positive temperature gradient and negative temperature gradient composite pavement structure temperature stress.By comparing the layout analysis of steel wire mesh and layout of steel wire mesh pavement structure temperature stress,we can get that under the temperature load,the wire mesh can fully absorb the close seams of asphalt layer bottom stress concentration,greatly reduces the maximum tensile force and maximum shear force,and reduce the asphalt layer on the open probability of reflective cracking and shear type reflection crack.In this paper,the galvanized steel wire net,geotechnical grille and geotextile were compared.The results show that the three indexes order are galvanized steel wire net > geotechnical grille > geotextile.And not distributed any layer compared to the layout of the steel wire mesh,geotechnical grille,geotextile after the pavement structure layers at the end of the maximum tensile stress decreases in 38.78% and 11.43% and 8.3%,AC the bottom layers of the maximum tensile stress value is the soil geogrid and soil geotextile 3.39 times,4.67 times;AC bottom layers of maximum shear stress and stress decreased 30.01% respectively,7.79%,4.41%,AC bottom layers of maximum shear stress and decreases are geogrid,geotextile 3.85 times,6.80 times;PCC slab top,the maximum bending heavy difference were reduced by 15.02%,3.61%,1.81%,PCC slab top,the maximum bending deflection difference decreases are geogrid,geotextile 4.16 times,8.30 times.Thus,wire mesh imposed reinforcing,anti cracking sandwich controlling horizontal open type,shear horizontal and vertical shear reflection crack can Force is superior to the geotechnical grille and the geotextile.