Experimental Study On Road Performance Of Asphalt Mixture Based On Composite Improvement

In view of the current situation of Tangshan heavy haul traffic,a sustainable modified asphalt with less energy consumption and maintenance is prepared.The composite modification of SBS and waste rubber powder can make use of waste tires,improve the performance of asphalt and reduce costs.The preparation of composite modified asphalt needs to consider multiple factors.The nested orthogonal test is used to optimize the process,and the road performance is verified from two aspects of asphalt and asphalt mixture in combination with disease,traffic volume and climate.1)The optimized preparation process of composite modified asphalt is to add 4%YH792 linear SBS into the base asphalt,shear for 0.5h at the speed of 4500 r / min,then add20% 60 mesh waste rubber powder and 0.3% lignin,adjust the speed to 4000 R / min,shear for 1h,and develop at 160 ℃ for 1H.2)A number of modified performance indexes of composite modified asphalt under the best process are tested and studied.It is found that its softening point is 79% higher than that of matrix asphalt,and its temperature sensitivity is reduced by 45.74%.It shows good hightemperature stability,separation,viscosity,and good low-temperature,elastic recovery,viscosity toughness and durability.It is inferred that it can effectively reduce the pavement deformation in the road performance,and has a certain self-healing ability.In the service process,it can greatly reduce the spalling and loosening of aggregate and reduce the cracking disease at the same time.3)The dynamic stability of the composite improved asphalt mixture can reach more than 10000,the residual stability is 94.1%,and the freeze-thaw splitting strength is 91.91%.It shows excellent high-temperature performance and water stability.It is verified that it can reduce the damage and deformation of the pavement and reduce the maintenance cycle under rain,snow and heavy load.In terms of low temperature properties,it has strong adhesion,good toughness and crack resistance,but poor ductility.Figure 54;Table 52;Reference 59...