Study On Temperature Parameter And Performance Of Asphalt Mixture Using Hot In-place Recycling Technology

Highway transportation is the fundamental and pioneering industry in China,and it has an important pushing effect on social and economic development.The highway work was in a stage of prosperity and development in recent years,and a large number of high-grade asphalt pavements put into use.But under the action of factors of load and climate,a large area of asphalt pavements in different degree of disease phenomenon need to be repaired.Hot in-place recycling technology can not only give full play to the residual value of the old material,but also repair the superficial pavement disease,which has become the hot spot of research with its good economic and environmental benefits.The aim of research on temperature parameter and performance of hot recycled asphalt mixture is to provide effective data for further popularization and application of HIR,so as to improve the performance of recycled pavement and give full play to the advantages of energy saving and environmental protection.The reasonable mixing and compaction temperature of recycled asphalt mixture using hot in-place recycling technology under different mixture ratio design are determined by experiments in the first place;then the influence of RAP content on the performance is studied;the reasonable construction technology is put forward and its economic and environmental benefits are evaluated finally.Combined with the rotary viscosity test and volume index control method,it is concluded that:the reasonable mixing and compaction temperature decreases with the increase of the RAP content and there is a regular change:when the RAP content increases by 10%,mixing and compaction temperature reduce by 5?.The pavement properties are studied based on determining the reasonable mixing and compaction temperature,when the RAP content increases from 70%to 100%,the water stability of hot recycled asphalt mixture is increased by 6.4%,the low temperature crack resistance is reduced by 15.3%,and the high temperature stability first increases and then decreases slightly.The economic benefits and environmental benefits of HIR are significantly better than the ordinary thermal mixing technology,when the RAP content increased from 70%to 100%,the CO2 emissions has reduced by 8.5%,the cost savings rate increased from 45.52%to 71.28%,and the initial investment recovery period of the equipment is short with significant benefits.