Study On The Performance Of Tires Pyrolysis Carbon Black Silane Coupling Agent Composite Modified Asphalt And Asphalt Mixture

At present,the number of motor vehicles in China has reached 393 million,the production of waste tires in China more than 20 million tons,and a sharp increase of 8%to 10%per year,which has caused serious pollution to the environment.At the same time,with the increasing domestic traffic,the existing asphalt pavement disease problems continue to aggravate,bringing great damage to the safety and property of China’s roads.In response to these two major problems,domestic and foreign researchers have proposed the use of tire pyrolysis carbon black(tires pyrolysis carbon black,TPCB)as a modifier for asphalt,TPCB is the main product obtained by high temperature cracking of waste tires,TPCB as a modifier added to asphalt and its mixture can significantly improve its high temperature stability and anti-aging properties,and TPCB can be added to asphalt and its mixes as a modifier to significantly improve its high-temperature stability and anti-aging properties,and TPCB is abundant,low cost,and can be used as waste to improve the ecological environment,but the effect on water stability and low temperature performance is not obvious.Silane coupling agent(SCA)is an organic compound with two polar groups,which can effectively enhance the bonding and stability of inorganic substances in organic matter.Combining the advantages and shortcomings of TPCB and SCA,the comprehensive performance of asphalt and its mixes can be improved by the compound addition between them.Firstly,in order to determine the best doping and preparation process,the test design was carried out using the response surface method based on the central composite design,and the gray correlation degree comprehensive evaluation method was introduced into the response surface analysis method,and the improved response surface design method was proposed,and the best formulation and preparation process of the composite modified asphalt were determined by this method:the doping of TPCB was 14.2%,the doping of SCA was 2.1%,and the shear time was 56.3 min.Secondly,the dynamic shear rheological performance test and flexural creep stiffness test were studied based on the composite modified asphalt determined by the optimized test method,and the modification mechanism was analyzed by infrared spectral analyzer and fluorescence microscope.The results show that TPCB can improve the rutting factor G*/sinδand reduce the phase angle 8 to make it more resistant to rutting,and also enhance its anti-aging performance.The infrared spectra of the composite modified asphalt and the matrix asphalt are basically similar,indicating that the mixing form of TPCB and SCA in asphalt is mainly physical co-blending.The fluorescence microscopy results prove that the incorporation of SCA makes the TPCB uniformly and stably dispersed in the matrix asphalt,which effectively enhances the modification effect of TPCB.Finally,the analysis of the composite modified asphalt mixture of high and low temperature and water damage resistance,the results show that the rutting test composite modified asphalt mixture dynamic stability than the matrix asphalt mixture increased by about 80%,can effectively improve the high temperature rutting resistance of asphalt pavement;small beam bending test composite modified asphalt mixture maximum bending and tensile strain is much greater than the TPCB modified asphalt mixture and can meet the specification requirements;water Marshall test and freeze-thaw splitting test results prove that the composite modified asphalt mixture has a more excellent resistance to water damage.