Study On Pavement Performance Of Anti-crack And Anti-aging Composite Modified Asphalt Mixture

Asphalt roads are widely used in China's high-grade road engineering due to their advantages such as smooth and continuous surfaces,low maintenance costs,convenient construction,and rapid opening of traffic.However,the asphalt pavement is susceptible to heat,oxygen and other environmental factors during the aging phenomenon,and looseness,rutting,cracks and other diseases appear,which seriously reduces the service level and service life of the pavement.Therefore,improving the anti-cracking and antiaging ability of asphalt mixtures is of great significance for extending the service life of roads and reducing their maintenance costs.In this paper,glass fiber asphalt mixture is used as the basic material,and hindered phenol antioxidant Iragnox 1010 is selected as its aging inhibitor.The Marshall test,semicircular bending test combined with Digital Image Correlation(DIC)technology and freeze-thaw splitting test are used to evaluate the road performance of the anti-cracking and anti-aging composite modified asphalt mixture.The main research conclusions are as follows:(1)Marshall test results show that the addition of Irganox 1010 will reduce the hightemperature strength of the glass fiber asphalt mixture before and after aging,but will increase its aging resistance,and the higher the amount,the better the aging resistance.(2)The results of the medium temperature semi-circular bending test show that when the amount of Irganox 1010 is 5%,the measured DIC tensile strain before and after aging is the largest and the aging index of tensile strain is closest to 1,indicating that the glass fiber asphalt mixture with 5% Irganox 1010 has the best deformation resistance and aging resistance.In addition,the fracture energy of the glass fiber asphalt mixture after longterm aging is higher than that without aging,indicating that the glass fiber asphalt mixture which is under moderate temperature conditions is beneficial to improve its crack resistance after long-term aging.(3)The results of low-temperature semi-circular bending tests show that the tensile strength of the glass fiber asphalt mixture before and after aging with 1% Irganox 1010 is slightly lower than that of the glass fiber asphalt mixture without Irganox 1010,but the DIC measured tensile strain and fracture energy were the highest,indicating that its toughness is highest and its crack resistance is the best at low temperature.Considering the aging index of tensile strain,the aging resistance of glass fiber asphalt mixture increases with the increase of the amount of Irganox 1010.(4)The results of the freeze-thaw splitting test show that the TSR value of the glass fiber asphalt mixture decreases after long-term aging,that is,the water stability performance becomes worse.Considering the TSR value,1% Irganox 1010 was the highest before aging,1% and 10% Irganox 1010 were the same after long-term aging,only a difference of 0.6%.The glass fiber asphalt mixture with 5% Irganox 1010 has the worst water stability performance,and the TSR value decreases the most before and after aging.(5)Comprehensively compare the road performance indicators of glass fiber asphalt mixture with different amounts of Irganox 1010 at different temperature,it is recommended that the optimal amount of Irganox 1010 be 1%.