Research On The Mechanical Behavior Of Asphalt Pavement Structure Of Cement Stabilized Macadam Bases Based On Slag Subgrade

The slag is the mined stone and its residual waste,which is the ideal material for filling the subgrade,with the advantages of high permeability,high compaction density,high strength and small settlement denaturation.As a typical semi-rigid base material,cement stabilized macadam,with high compressive strength and low tensile strength,is easily damaged by tensile cracking in road engineering.Slag subgrade material is the point of penetration in this paper,to study the slag water stability of roadbed asphalt pavement structure mechanical behavior is of great theoretical and practical value.First of all,this paper studies the gradation of slag and design its optimal gradation.Considering the water content as one of important factors influencing slag subgrade resilient modulus and stability,this paper mensurate resilient modulus of slag with cyclic compression method.The results show that Slag modulus values are far greater than the standard design of subgrade resilient modulus value;There is peak relationship between slag subgrade resilient modulus and water content;Water content has little effect on modulus of resilience optimal gradation of slag.It is suggested to adopt the optimal distribution of slag as subgrade filling material.Secondly,this paper also designs an optimal gradation of the cement stabilized macadam.The results of the unconfined compression strength,compressive resilience modulus and uniaxial tensile strength tests prove that the optimal gradation of cement stabilized macadam has the best mechanical properties.The binary linear function and the Farazdaghi-Harri model function can well fit the stress-strain relationship of the cement stabilized macadam through the uniaxial tensile test.Based on the damage mechanics theory and the Sidoroff model,It obtains the tensile damage constitutive equation with a new damage factor.Finally,this paper puts the test results of the slag and the cement stabilized macadam in the pavement layer material parameters established by ABAQUS,to do research on mechanical behavior of slag roadbed of cement stabilized macadam asphalt pavement structure.By ABAQUS simulation,with the increase of resilient modulus of subgrade,the parameters of linear variation trend of cement stable pavement slag subgrade gently.Slag road pavement thickness can be appropriately reduced,the sensitivity can be appropriate to reduce the influence of overloading on cement stable asphalt pavement structure parameters as well.The main innovations of this paper is as follows:(1)Mensurate resilient modulus of slag with cyclic compression method(2)Grip design for uniaxial tension of cement stabilized macadam(3)Tension damage constitutive equation of cement stabilized macadam...