Study On The Effect Of Anti-stripping Agent On The Performance Of Crumb Rubber Modified Asphalt And Mixture

Modified asphalt with waste rubber powder can not only improve the high and low temperature performance and anti-aging performance of asphalt,reduce cracking of asphalt pavement,improve comfort,safety and pavement service life of vehicles,reduce traffic noise,but also recycle waste tire rubber and reduce environmental pollution caused by solid waste.Its series of advantages are in line with the requirements of green pavement and sustainable development in China.Because of its excellent road performance,resource saving and cost reducing,rubber powder modified asphalt is gradually becoming a research hotspot in the field of road engineering materials.Although current research shows that the water stability of asphalt mixture can be slightly improved by using rubber powder modified asphalt in wet process,it can not meet the requirement when used in permeable pavement and other pavement with high water stability performance requirements.Ther efore,in order to improve its pavement performance,anti-stripping agent is selected to improve its water damage resistance.The main contents of this paper are as follows:The infrared spectra of anti-stripping agent(M1?T9?LOF-6500)and rubber powder modified asphalt and the conventional physical properties(viscosity,softening point,penetration,ductility),rheological properties and aging properties of anti-stripping agent and rubber powder modified asphalt before and after aging were tested.The infrared spectrum test results show that the addition of anti-stripping agents will react with anhydride in the modified asphalt to produce organic gel,thereby improving the properties and chemical stability of the asphalt.In addition,physical properties,rheological properties and aging properties can be found to improve the high temperature performance and anti-aging performance of rubber powder modified asphalt,but it is not conducive to low temperature performance;It can be seen from PG classification that anti-stripping agents have no effect on the high-temperature grade of rubber powder modified asphalt,but LOF-6500 will reduce the low-temperature grade by one grade.In order to quantitatively evaluate the effect of different kinds and dosages of anti-stripping agents on the adhesion of rubber powder modified asphalt,surface free energy(SFE)method was used to analysis.The experimental results show that the addition of anti-stripping agent can improve the adhesion work and the stripping work of rubber powder modified asphalt.It shows that the anti-stripping agent can improve the adhesion between rubber powder modified asphalt and aggregate in both dry and wet conditions.Finally,the influence of anti-stripping agent on the high temperature performance,low temperature performance and water stability of rubber powder modified asphalt mixture was tested,and the water stability of the mixture was compared with the previous results of adhesion.The results show that the addition of anti-stripping agent can improve the high temperature deformation resistance and water damage resistance of rubber powder modified asphalt mixture,but reduce its low temperature crack resistance.By comparing the tensile strength ratio(TSR)results with the surface free energy results,it is found that the dosage is different from that of surface energy results when the maximum TSR values of different kinds of anti-stripping agents were obtained,indicating that adhesion is not the only condition for evaluating the w ater stability of asphalt mixtures.