Self-healing Law Of Aggregate Asphalt Interface Strength And Its Influence On Healing Property Of Mixture

Research on asphalt pavement shows that the damaged pavement can achieve a certain degree of self-repair in a certain environment,and this ability of the damage repair directly affects the service life of the pavement.At present,some progress had been made in the research on the self-healing of asphalt,asphalt-aggregate and asphalt mixture.However,due to the influence of rainfall and aging factors in the actual use of pavement,the self-healing law of the interface strength of asphalt-aggregate under the influence of water immersion and aging is still unclear,so it is necessary to use the test method for the further research.Therefore,this article takes self-healing law of aggregate asphalt interface strength as the research object,studying the influence of healing time and temperature on the self-healing strength of aggregate asphalt,determining the main self-healing curve on the interface strength of aggregate asphalt's self-healing by analyzing the relationship between the effect of healing time and temperature for the self-healing of aggregate asphalt,of which making use to determine the best healing time and temperature and on the basis of that to study the impact of healing pressure,immersion time,salt solution concentration and aging degree for the self-healing property of aggregate asphalt.At the same time,in order to analyze the influence of asphalt-aggregate interface on the self-healing of asphalt mixture,the self-healing law of the mechanical properties of asphalt mixture was simulated and analyzed by means of mesoscopic finite element method.The following conclusions are drawn:Firstly,the healing time,temperature and pressure have a positive effect on the self-healing of the bonding interface strength of asphalt-aggregate;At any temperature,the longer the healing time,the better the performance of strength healing,and the higher the healing temperature,the better the strength of self-healing performance.Under the same healing temperature and healing time,the healing pressure has a significant effect on the self-healing of the interface strength of asphalt-aggregate.Secondly,the time-temperature equivalence principle is suitable for describing the self-healing property of the bonding interface strength of asphalt-aggregate,and the time-temperature shift factor can be determined by trial calculation based on the principle of minimum residual sum of squares.Thus,Compertz model was used todetermine the self-healing properties of interface strength at different temperatures and healing times.Thirdly,immersion time,salt solution concentration and asphalt aging have negative effects on the strength of the interfacial healing;The longer the soaking time,the worse the healing performance.The higher the concentration of salt solution,the lower the self-healing property of the interface of asphalt-aggregate.The self-healing performance of the interface of asphalt-aggregate is obviously reduced due to asphalt aging.Fourthly,both the ability of the strength recovery and asphalt mixture fracture recovery are higher than the corresponding interface healing performance of asphalt-aggregate,and the fracture recovery rate is slightly higher than the strength recovery rate.