| With the increase in the number of cars in my country,the accumulation of waste rubber and waste plastics has caused increasing environmental harm,and the harmless treatment of solid waste has become an urgent problem to be solved.This paper conducts detailed tests on the road performance of rubber-plastic composite asphalt,and comprehensively evaluates its performance.Combined with the different mechanical response characteristics of the upper and middle surface layers of the pavement structure,the application research of rubber-plastic modified asphalt and asphalt mixture was carried out to provide technical support for the promotion and application of the rubber-plastic composite modified rubber asphalt pavement technology of different structural layers.The main research contents of this article are as follows.Toughened and high-strength rubber-plastic composite modified asphalts were selected for testing,compared with SBS modified asphalts,to test the conventional performance index and SHRP index of asphalt.The test results show that the penetration of the high-strength rubber asphalt is within 35(0.1 mm),which is significantly smaller than the other two asphalts,and the softening point is less than that of the SBS modified asphalt,but it can meet the requirements of the ID modified asphalt;the dynamic viscosity reaches SBS modified asphalt is more than 2 times,G*/sinĪ“ is obviously larger than the other two asphalts.The high-temperature performance of toughened rubber-plastic modified asphalt and SBS modified asphalt are close,and the low temperature performance is better than SBS modified asphalt.The aging test results show that the penetration ratio of the high-strength type is 77.2%,which is higher than that of the other two types of asphalt;the ductility ratio of the toughened type is 94.1%,which is higher than the other two types of asphalt.Rubber powder and plastic are mixed into the asphalt Can effectively improve the anti-aging ability of asphalt.Due to the high viscosity of the rubber-plastic composite modified asphalt,it is beneficial to increase the thickness of the oil film on the surface of the aggregate and improve the durability of the asphalt mixture;but too high viscosity is unfavorable to the construction,and it needs to be balanced when selecting the rubber-plastic modified asphalt Road performance and construction and ease of use.Considering the characteristics of high tensile stress at the bottom of the upper layer of asphalt pavement in my country,SMA-13 asphalt mixture was designed using toughened rubber-plastic asphalt to study the road performance.The test results show that the leakage of rubber-plastic asphalt is significantly weaker than that of SBS modified asphalt,and it can be mixed with or without fibers in the design process of mix ratio.Comparing the performance of toughened rubber-plastic asphalt mixture and SBS modified asphalt mixture,we can see that the high-temperature performance and water stability of toughened rubber-plastic asphalt are lower than that of SBS modified asphalt mixture,and the low-temperature performance,crack resistance and fatigue resistance are more it is good.In addition,the initial dynamic friction coefficient of rubber-plastic asphalt mixture is greater than that of SBS modified asphalt mixture,which has good anti-slip properties and is suitable for use on the upper layer of asphalt pavement.The road performance of AC-20 asphalt mixture prepared by high-strength rubber-plastic asphalt and SBS modified asphalt is compared.The results show that the low-temperature performance of high-strength rubber-plastic asphalt mixture and SBS modified asphalt mixture is equivalent.The water stability and high temperature performance of the mixture are significantly improved.In addition,the shear strength of the high-strength rubber-plastic modified asphalt mixture is 1.18 times the shear strength of the SBS modified asphalt mixture.The high temperature performance is significantly better,and it is more suitable for the rutting of the middle surface layer.Paving the test road of rubber-plastic modified asphalt mixture,summarizing the construction process,and testing the performance of the test road.The results show that the construction temperature of rubber-plastic modified asphalt mixture should be strictly controlled to reduce the segregation of the mixture;the flatness,anti-skid performance and water permeability of the test road are at the same level as the ordinary modified asphalt pavement,and all can meet the specifications Claim. |
