Study On Mechanical Properties And Optimization Design Of Glass Fiber Reinforced Plastic (GFRP) Dowel Bar

According to?Statistical Bulletin of Transportation Industry Development?of transportation show that,by the end of 2016,highway mileage of China reached 469.63 million kilometers.Under the effect of normal vehicle cycle,the service life of concrete pavement is usually 20 to 40 years,however,it is worth noting that there are three big problems of concrete pavement to make the pavement premature failure,including broken slab?faulting of slab ends?joint damage.In order to make the cement road surface can meet the design service life,and improve the load transfer ability of dowel bar in the pavement joint,so it is particularly important to study of its mechanical properties.From theoretical perspective,the second chapter of this paper chooses the single parameter foundation model,and analysis the maximum bending?tensile stress under different load positions of pavement.According to the most unfavorable load under different position,calculating the influence of modulus,size,section forms of dowel bar to deflection value of the seams?GFRP dowel bar relative deflection of adjacent road slab and the contact stress of concrete interface.According to composite material technology and construction method in the domestic,From the influence factors of mesoscopic GFRP dowel bar,we study the change of fiber volume content on the influence of dowel bar elastic modulus of composites from the perspective of theory.GFRP dowel bar is optimized design using the ABAQUS finite element numerical simulation method,this article establishs concrete pavement-composite 3D finite element model of dowel bar system with different filament wound Angle and fiber volume content,and researches on the influence of concrete pavement deflection and dowel bar the maximum compressive stress of the interface and the single maximum shear dowel bar transferred in the pavement joint.Finally,anisotropic composite material has a better dowel bar of filament winding Angle and the fiber volume content under wheel load,then,the design of composite material dowel bar reference opinions are put forward.Under the condition of the axial load?the temperature gradient and temperature load coupling,we study the mechanical property of steel dowel bar and GFRP dowel bar,then,selecte the optimal fiber volume content 0.65 and the filament winding Angle 45° degrees of GFRP dowel bar to carry on the numerical simulation from the microscopic view,and analysis the bearing performance of GFRP dowel bar under the three kinds of working condition compared with steel dowel bar.Finally,the last part study different modulus,radius,the length of the circular GFRP dowel bar and elliptical-shaped GFRP dowel bar on the influence of maximum deflection of pavement,the maximum compressive stress of concrete dowel bar interface,Shear force of single GFRP dowel bar transmission in the joint by means of numerical simulation analysis,and the design of the GFRP dowel bar reference opinions are put forward.In addition,compared to the same cross section area of the circular GFRP dowel bar and elliptical-shaped GFRP dowel bar mechanical properties under the action of load ?temperature gradient separately and the coupled action of load and temperature,selecting the optimal form of cross section.