Influence of new added asphalt grade on strength and fatigue performance of high percentage of RAP mixtures(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2017年03期
- Page:
- 9-15
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Influence of new added asphalt grade on strength and fatigue performance of high percentage of RAP mixtures
- Author(s):
- LI Ming-xin; WANG Xuan-cang
- School of Highway, Chang’an University, Xi’an 710064, Shaanxi, China
- Keywords:
- road engineering; asphalt grade; RAP; strength; fatigue performance
- PACS:
- U414.75
- DOI:
- -
- Abstract:
- In order to study the influence of new added asphalt types’ performance difference on strength and fatigue performance of high percentage of RAP (reclaimed asphalt pavement) content recycled asphalt mixture, three different types of recycled asphalt mixtures were prepared in this study. The first mixture was AC-20 asphalt mixture made from new aggregates and 70# asphalt. The other two mixtures were AC-20 recycled asphalt mixtures with RAP content of 50% and addition of 70# and 90# asphalt, respectively (abbr. AC-20 reference group, AC-20-50%RAP-70#, AC-20-50%RAP-90#). Three mixture sets used the same target grading design and asphalt content. Performance of asphalt mixture was analyzed by strength and fatigue test. Strength of asphalt mixture was evaluated by uniaxial compression test and splitting test at different temperatures. Fatigue performance was evaluated by the UTM four-point bending fatigue test with controlled strain. Feasibility of using formula method to predict fatigue performance of recycled asphalt was also investigated based on the change of penetration and softening point of recycled asphalt. The results show that strength of recycled asphalt mixture can be improved by adding 50% RAP, and strength of asphalt mixture decreases with the increase of test temperature. Within the test temperature range, strength order of the three groups does not change with the increase of test temperature. AC-20 recycled asphalt mixture by adding 70# asphalt ranks the highest in strength. Fatigue performance of the regenerated mixture is related to the addition of the new asphalt type. AC-20 recycled mixture by adding 90# asphalt has the best fatigue performance, while fatigue life of the recycled mixture with 70# asphalt is lower than that of the reference asphalt mixture set. New asphalt with an appropriate asphalt grade can improve the fatigue performance of recycled asphalt mixture effectively.
Last Update: 2017-06-06