Effect Of Different Aging Methods On The Performance Of Rubber-modified Asphalt And Its Mixes

In the current road transport industry,due to the existence of a large number of scrap tires,not only will have an impact on the surrounding ecological environment,but also will lead to a great waste of resources.The modified asphalt made of SBS mixed with rubber powder has excellent comprehensive quality,low price and wide application fields,and is a powerful tool for the development of road transportation in China.Therefore,the recycling of waste rubber is an effective conservation measure.The waste rubber can be used in road construction after processing,which can not only extend the service life of the road,but also reduce the time and effort of maintenance,which is a good way of resource utilization at present.This thesis is centered on the preparation of high-doped rubber powder modified asphalt and the analysis of its aging properties and the basic properties of its asphalt mixture.Firstly,the raw materials,the process of SBS rubber modified asphalt and the modification mechanism are analyzed.The different processes of SBS rubber compound modified asphalt were discussed,and its various process treatments were elaborated.Then the technical requirements for the preparation of highly blended rubber modified asphalt,the formulation design was carried out,and finally the better preparation process of highly blended rubber modified asphalt was obtained,the better formulation is: viscosity reducer 1.25‰,SBS 1%,reinforcing resin 5%,cross-linking agent 0.25%(all percentages are the mass fraction of asphalt 70),the better swelling temperature should be set at 200～210 ℃,the swelling time should be set at 30～40 min,and the shear speed should be 7000 rpm.Subsequently,the high-doped rubber-modified asphalt was tested in high and lowtemperature performance tests,and the ageing performance analysis(thermal-oxidative ageing,photo-oxidative ageing,moisture ageing)was carried out on the prepared highdoped rubber-modified asphalt.Finally,we obtained the best performance of 30%rubber-modified asphalt both in the ageing process and in the high and low-temperature performance tests.Microscopic analysis of asphalt,30% rubber-modified asphalt was obtained to have the best stability.Then various asphalt mixes were analyzed for high temperature,low temperature,water stability,fatigue performance and other tests,and the best indicators were obtained for 30% rubber-modified asphalt.And then study the effect of different mixing building storage times on the performance of high-doped rubber asphalt mixes,it is concluded that the extension of storage time will reduce the performance of asphalt mixes.According to the mixture’s low temperature,and water stability performance test results,to meet the performance requirements and combined with the asphalt mixture storage 8 h after the fatigue life significantly reduced,it is recommended that the storage time does not exceed 4.4 h.Then,the influence of storage time in different mixing houses on the high content rubber modified asphalt extracted from the mixture was studied.It was found that at the same mixing temperature,the increase in storage time would aggravate the ageing of the base properties of the highly blended rubber asphalt and reduce its high and lowtemperature properties.190 °C was the lightest testing temperature for the base properties.Conclusion of the results,analysis of the research process,the current shortcomings of the study of highly blended rubber-modified asphalt and the prospects.