Research On The Performance Of Waste Tire Rubber And APAO Modified Asphalt Mixture

In order to improve the performance and service life of asphalt pavement.The application of high performance polymer modified asphalt to improve the performance of the mixture is a research hotspot in recent years.Waste Tire Rubber(WTR)modified asphalt has been widely used in road engineering due to its good road performance and economical environmental protection.In order to further improve the performance of WTR modified asphalt,research on composite modified asphalt is a new trend.Hence,research proposes a new polymer modified asphalt which modified by WTR and Amorphous Ploy Alpha Olefin(APAO).The WTR/APAO modified asphalt was used as the binder to explore its effect on the performance of asphalt mixture.Previous studies of WTR/APAO modified asphalt have shown that it is a highly viscous and highly elastic asphalt with good hi gh and low temperature properties,storage stability and anti-aging properties.In order to further explore the advantages and disadvantages of its road performance,the research on the properties of WTR/APAO modified asphalt mixture was proposed.Firstly,12% WTR+4%APAO and 15%WTR+4%APAO were selected as the main research objects.And the performance of AC-13 C type mixture with WTR/APAO modified asphalt was studied.The research was carried out by experiments on volume index,modulus index,high and low temperature performance,water stability performance,fatigue performance and anti-aging properties.The results show that WTR/APAO modified asphalt mixture has excellent high temperature stability,permanent deformation resistance,water stability,aging r esistance and relatively good fatigue performance.Combined with various performance studies,the study concluded that 15% WTR+4% APAO modified asphalt mixture has better performance and is suitable for asphalt pavement.Secondly,based on the characteristics of WTR/APAO modified asphalt,the application research of 15% WTR+4% APAO modified asphalt Stress-absorption interlayer(SAI)is proposed.The research object is 70# matrix asphalt SAI,SBS SAI,WTR SAI and WTR/APAO SAI.The high and low temperature properties,water stability and aging resistance of four SAIs mixture were investigated.Then the interlayer adhesion properties of the combined test pieces of three modified asphalt SAIs and AC-13 mixture were studied.The reflection cracking resistance of the SAI were studied by Overlay Test(OT)and Paris' Law.The results of SAI show that the WTR/APAO SAI mixture has good high temperature performance,water stability and anti-aging properties.But the addition of APAO will adversely affect the low temperature performance of the WTR/APAO SAI.The WTR/APAO SAI has excellent interlayer adhesion properties.The cycle number of OT and the indicators A and n of Paris`Law were used as the evaluation indexes of the reflection cracking resistance of the SAI.It has been found that the WTR/APAO SAI have better reflection cracking resistance and slower crack propagation rates.The WTR/APAO SAI is an excellent new type of stress-absorption interlayer.Under the same stress,WTR/APAO SAI is more resistant to reflection cracks.However,the SAI may not be suitable for use in cold and high mountain areas.