Research On Mechanical Performance Of Inverted Asphalt Pavement Structure With Graded Crushed Stone In Fushun

Semi-rigid base is widely used in the pavement structure in Fushun,duo to it has high strength and stiffness,good bearing capacity and load diffusion ability,fatigue of driving resistance and so on.With the widely use of semi-rigid base,more and more questions appear and can not be solved.People begin to focus on new type of pavement structure,such as flip chip type pavement structure and flexible base.According to tactual situation in Fushun,people carry out indoor test about road performance of flip chip type pavement structure,meanwhile mechanical response and fatigue performance are studied.Through laboratory test,the result shows that the dynamic rebound modulus of skeleton dense graded aggregate is 112.7MPa,and the static modulus of resilience is334MPa;the dynamic rebound modulus of continuous graded crushed stone is116.5MPa,and the static modulus of resilience is 362 MPa.Through CBR test,the results show that the CBR values of skeleton compact and continuous Graded Macadam are 123.8% and 101.75% respectively,and the CBR value of skeleton dense graded macadam is larger,which proves that it has good bearing capacity.Permanent deformation is studied through MTS810,the results show permanent deformation of graded gravel skeleton dense type and continuous level associated with graded crushed stone increase slowly with number increasing,and permanent deformation remain unchanged when the number is close to 1000.Accumulative deformation rate increases with Stress increasing,permanent deformation remain unchanged when the number is close to certain value.In simulation of ABAQUS,flip-type pavement structure can prevent semi-rigid base of reflection cracking,at the same time,it can reduces the chance of semi-rigid base cracking fundamentally through uniform stress.Mechanical response is carried out by changing thickness and modulus,the results show thickness of 11~14cm and modulus of 350~450MPa are suitable.Fatigue analysis of flip chip type and semi-rigid base are carried out through NSOFT.Flip chip type is bigger than semi-rigid base in the surface damage,but they are similar in cement stabilized gravel layer.However,the value of surface damage in the same order of magnitude which show fatigue performance is similar between flip chip type and semi-rigid base.The results proposed by this paper lay a certain theoretical foundation for the application of flip-type pavement structure the popularization and the laid certain theoretical foundation for the design,would provide reference for the pavement design and further research work.