Research On Road Performance Of Warm Mix Recycled Asphalt Mixture

With the rapid development of China’s national economy,high-grade roads have entered a period of vigorous development and maintenance.A large number of high-grade roads have entered the end of use.When overhauling high-grade asphalt roads,a large amount of waste asphalt and waste will be generated.Aggregate,and now China’s recycling of waste roads is only about 20% to 30%,so the low utilization of waste roads not only caused a lot of waste of resources and generated a large amount of construction waste.Warm mixing and recycling of waste asphalt pavement can not only promote the secondary utilization of non-renewable resources,but also reduce the mixing temperature and reduce greenhouse gas emissions,and has a good application prospect.This paper firstly tests the road performance of aged asphalt,recycled asphalt and warm mixed recycled asphalt by three conventional test indexes,rotational viscosity test,rutting factor test,fatigue factor test,multi-stress repeated creep test and low temperature creep trabecular test.the study.The test results show that after the aging of the asphalt,the penetration and elongation decrease to nearly 50%,and the softening point is increased to 18%,which indicates that the low temperature performance of the asphalt is weakened after aging,the high temperature stability is improved,and the high temperature is low after regeneration.The performance recovery is up to 90%,the performance of the warming agent is 30% higher than that of the recycled asphalt,and with the increase of the aged asphalt,the improvement effect is worse and worse,indicating the aging in the warm mixed asphalt.The proportion of asphalt is too high,too high will cause its road performance can not meet the requirements.On the basis of the research on the warm mixed recycled asphalt binder,the road performance of the mixed aging mixed asphalt mixture with different RAP materials was studied by the mixture test.The results show that the addition of warming agent to the high temperature stability of the mixture With a certain weakening,with the increase of RAP content,the dynamic stability of the mixture is gradually increased,indicating that the addition of the old aggregate can improve the dynamic stability of the mixture,so that its regeneration effect is weakened;The maximum bending strain of aging asphalt has a certain increase,and the maximum bending strain of asphalt low temperature is further improved after the mixing of warming agent,and the low temperature stability of the RAP old aggregate decreases by 15% for each 10% increase;After the regeneration and warm mixing,the water stability performance is improved.The test results of the mixture show that the addition of the warming agent makes the asphalt mixture significantly improved in low temperature and water resistance,and the regeneration effect is good,but the amount of RAP old aggregate is not too much,and it is relatively optimal at 40%.The short-term and long-term performance tests of the pavement were carried out on the completion of the paved road and the completion of the test.The test results show that the pavement is completed and the road surface performance of the warm mixed regeneration pavement is good after the opening of the traffic.