Asphalt Binder Property and Adaptability Based on PG Grading in Severe Cold and High Altitude Regions
To solve the problem of insufficient performance of asphalt in the severe cold and high altitude regions,based on the characteristics of topography,geomorphology and climate,and relying on the 30-year meteorological data observed by several meteorological observation stations along the Golmud-Nagqu section of Beijing-Tibet expressway,the statistical analysis and calculation were carried out on the geomorphology,climatic characteristics,altitude,and traffic load data.The adaptability of PG grading method for asphalt binder in high-altitude regions with large temperature differences was explored.The result indicates that the LTPP high temperature calculation model is modified based on the field monitoring results in Qinghai-Tibet region.The formula for calculating high temperature of asphalt binder in this region is proposed to improve the reliability of the formula.In Golmud-Nagqu section,the recommended PG classification value of asphalt binder reaches the highest PG 76-22.In the severe cold and high altitude region,the effect of elevation increase on low temperature cracking resistance of asphalt should be fully considered.The low temperature grade should be increased by 1 to 2 grades.It is recommended to use SBR Ⅱ-A modified asphalt in Nagqu area,and to use SBS modified asphalt in Golmud area.In Tuotuohe and Wudaoliang areas,it is recommended to develop UV-resistant modified asphalt,and use higher grade base asphalt to carry out SBS/SBR composite modification on asphalt for its applicability study.The study result provides basis for the material development technology,construction technology improvement and engineering application of asphalt binder in severe cold and high altitude regions.It is conducive to improving the construction quality of asphalt pavement,and extending the service life.
road engineeringhigh and low temperature propertiesPG gradingasphaltstrategic highway research program(SHRP)
NETL
NSTL
万方数据
