When the plant-mixed thermal regeneration technology is adopted for the waste asphalt pavement mixtures,its performance can basically reach the level of freshly-mixed asphalt concrete,which can be used for paving the ...When the plant-mixed thermal regeneration technology is adopted for the waste asphalt pavement mixtures,its performance can basically reach the level of freshly-mixed asphalt concrete,which can be used for paving the middle and lower layers of road pavements of various grades.Through the research and application of plant-mixed thermal regeneration technology based on China's Kunming-Yuxi Expressway Pavement Overhaul Project,this paper summarizes relevant technical points and effectively advocates the promotion and application of this technology in highway maintenance.展开更多
Hot recycling of reclaimed asphalt pavement(RAP)from replacement of deteriorated asphalt pavements is a widespread technique,and able to ensure clear economic and environmental benefits.For this reason,paving industri...Hot recycling of reclaimed asphalt pavement(RAP)from replacement of deteriorated asphalt pavements is a widespread technique,and able to ensure clear economic and environmental benefits.For this reason,paving industries,agencies and researchers are spending significant efforts in order to maximize such advantages by increasing the amount of RAP within new asphalt mixtures.Nevertheless,adequate performance of recycled mixtures must be guaranteed despite the re-use of high amounts of RAP which involves the presence of aged,oxidized and stiffened binder.In this perspective,the present study aimed at evaluating the rheological properties at mid-service and high-service temperatures of bituminous blends composed by 40%of virgin binder and 60%of aged rejuvenated bitumen(simulating the aged hard bitumen coming from the RAP).Such proportion was selected to represent a high recycling rate of RAP(about 60%of the total weight of aggregates,RAP included).A chemical commercial additive at the liquid state was selected as rejuvenator;it was dosed at the optimum content based on empirical and rheological preliminary characterization.The performance of the recycled blend was then compared to that of a virgin reference bitumen.Dynamic shear rheometer tests were carried out to determine the master curves and the failure characteristics(at mid and high service temperatures)of the selected binders.The effect of aging(related to the durability over the material lifetime)was also studied analyzing binders’responses in unaged,shortterm and long-term aged conditions.Overall,experimental findings demonstrated the efficacy of the rejuvenation of recycled binders containing very high amount of aged bitumen.展开更多
文摘When the plant-mixed thermal regeneration technology is adopted for the waste asphalt pavement mixtures,its performance can basically reach the level of freshly-mixed asphalt concrete,which can be used for paving the middle and lower layers of road pavements of various grades.Through the research and application of plant-mixed thermal regeneration technology based on China's Kunming-Yuxi Expressway Pavement Overhaul Project,this paper summarizes relevant technical points and effectively advocates the promotion and application of this technology in highway maintenance.
基金funded by the Department of Civil,Environmental and Architectural Engineering(ICEA)of the University of Padova(project BIRD182754)。
文摘Hot recycling of reclaimed asphalt pavement(RAP)from replacement of deteriorated asphalt pavements is a widespread technique,and able to ensure clear economic and environmental benefits.For this reason,paving industries,agencies and researchers are spending significant efforts in order to maximize such advantages by increasing the amount of RAP within new asphalt mixtures.Nevertheless,adequate performance of recycled mixtures must be guaranteed despite the re-use of high amounts of RAP which involves the presence of aged,oxidized and stiffened binder.In this perspective,the present study aimed at evaluating the rheological properties at mid-service and high-service temperatures of bituminous blends composed by 40%of virgin binder and 60%of aged rejuvenated bitumen(simulating the aged hard bitumen coming from the RAP).Such proportion was selected to represent a high recycling rate of RAP(about 60%of the total weight of aggregates,RAP included).A chemical commercial additive at the liquid state was selected as rejuvenator;it was dosed at the optimum content based on empirical and rheological preliminary characterization.The performance of the recycled blend was then compared to that of a virgin reference bitumen.Dynamic shear rheometer tests were carried out to determine the master curves and the failure characteristics(at mid and high service temperatures)of the selected binders.The effect of aging(related to the durability over the material lifetime)was also studied analyzing binders’responses in unaged,shortterm and long-term aged conditions.Overall,experimental findings demonstrated the efficacy of the rejuvenation of recycled binders containing very high amount of aged bitumen.
