Research On The Performance Of Modified Asphalt Mixed With Nano-ZnO And Trinidad Lake Asphalt

This paper adopts the method of compounding nanometer zinc oxide with lake asphalt,using the absorption and shielding effect of nanometer zinc oxide particles on ultraviolet rays and the anti-radical oxidation resistance of lake asphalt.Comprehensively improve the anti-thermal oxygen aging and photo-oxidative aging resistance of SBS modified asphalt,and overcome the shortcomings of seeking prevention and control measures for thermal aging and photo aging-alone.Composited modified asphalts with different modifier contents were prepared by high-speed shearing method,and laboratory tests were conducted.The main conclusions are as follows:With the addition of nano zinc oxide and lake asphalt,the conventional physical properties of SBS modified asphalt can be greatly improved.It only adversely affects the ductility of SBS modified asphalt.The viscosity of composite modified asphalt will increase sharply with the increase of lake asphalt content.In order to reduce the drop in low-temperature performance and construction difficulties caused by the amount of lake asphalt,comprehensively considering the effect of the amount on the performance of SBS modified asphalt,it is appropriate to control the amount of lake asphalt at 25%.In the dynamic shear rheology test,at the same temperature,both lake asphalt and nano zinc oxide can increase the complex modulus of composite asphalt and the stiffness of composite asphalt,and the phase angle of composite modified asphalt is reduced.The high temperature performance has been greatly improved.The bending beam rheological test shows that the addition of 25%lake asphalt can reduce the low temperature crack resistance of SBS modified asphalt to a certain extent,but its PG low temperature classification temperature is-16 ℃,which can still meet the requirements of most regions.In the aging test,due to the organic combination of nano zinc oxide and lake asphalt,the penetration ratio and phase angle aging index of the composite modified asphalt increased significantly,the softening point increase and the complex modulus aging index decreased significantly.The effect of performance degradation caused by various aging conditions is better reduced,and the basic physical properties of SBS asphalt and the changes in rheological properties before and after aging are comprehensively considered.Finally,3%nano zinc oxide+25%Lake asphalt’s SBS composite modified asphalt(ZTS composite modified asphalt)is used as the recommended solution in this paper.The temperature sensitivity of the ZTS composite modified asphalt and the SBS modified asphalt was studied.Using the medium and high temperature viscosity temperature curves of the two asphalts,it was found that the relationship between the viscosity and temperature of the two asphalts meets the WLF equation at medium temperature.The temperature sensitivity of ZTS composite modified asphalt before and after aging is lower than that of SBS modified asphalt.The addition of nano zinc oxide and TLA greatly reduced the Ic growth rate of ZTS composite modified asphalt after aging,and delayed the conversion process of asphalt to gel asphalt.Infrared spectroscopy results showed that the addition of TLA and nano zinc oxide effectively inhibited the formation of carbonyl groups and the cleavage of C=C double bonds in butadiene.ZTS composite modified asphalt and its mixture have better road performance.Although the production cost is slightly higher than SBS modified asphalt,ZTS composite modified asphalt mixture improves the durability of asphalt pavement.The service life of the asphalt pavement has been greatly extended,which can save the maintenance and repair costs during the entire life cycle.Its economic,social and environmental benefits are high,and it has a good application prospect.