Analysis Of Fatigue Life In Asphalt Pavement Based On Different Sealing Technology

The lower seal layer refers to the thin layer of asphalt mixture set between the old road asphalt surface layer or asphalt mixture surface layer,and the inorganic binder stabilized material base in the asphalt pavement structure,which has the functions of waterproof,bonding structure layers and stress absorption.It is often used in pavement maintenance engineering.In the structural repair engineering,the type of interlayer material will affect the service life of the old road as the connection layer between the base course and the underlying course.At present,the common types of lower seal technology are rubber asphalt macadam seal,emulsified asphalt macadam seal,slurry seal,and hot asphalt macadam seal.However,there is no clear conclusion to quantitatively evaluate the impact of these four technologies on the service life of inorganic binder stabilized base asphalt pavement.For this reason,this paper studies the influence of different sealing technology on the service life of the inorganic binder stabilized material base asphalt pavement.Aiming at the four sealing technology applied in the structural repair project of Liaoning ordinary highway asphalt pavement,through the field investigation,indoor test,and corresponding theoretical analysis,this paper quantitatively evaluates the effect of different sealing technology on the old in the structural repair project The influence of road service life guides the scientific and reasonable selection of lower seal technology in the future.Firstly,according to the structural test model of asphalt pavement in structural repair engineering,the performance tests of interlayer connection are carried out respectively.To compare the performance of different treatment technologies and provide parameters for theoretical analysis.Secondly,based on the field investigation of the application effect of different sealing technology in Liaoning Province,the disease types and characteristics of asphalt pavement under different sealing technology are described.The core samples of different types and severity of diseases are drilled,the damage condition of the base course is counted,and the mapping relationship between the pavement diseases and the technical condition of the base course is established.Third,combined with the investigation data,the base damage index BCI,which reflects the condition of the old road base,is proposed.The resilient modulus test is carried out on the core sample of the old road base at the typical diseases,the distribution rule of the BCI and the old road base modulus is analyzed,the decay curve of the old road base modulus is fitted,and the value range of the base modulus of the old road inorganic binder stabilized material is determined.Finally,the Abaqus finite element model is established to simulate the stress distribution of pavement under different lower seal technology,and the influence of connection coefficient and resilient modulus of different lower seal on the maximum tensile stress and strain at the bottom of inorganic binder base course and the maximum shear stress between base courses is analyzed.The fatigue life range of Asphalt Pavement Based on inorganic binder stabilized material under different connection conditions between base courses is calculated,and the suitable time for structural repair under the technology of lower seal layer is put forward.