Mechanism research on additives of high modulus asphalt mixtures(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2015年06期
- Page:
- 42-48
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Mechanism research on additives of high modulus asphalt mixtures
- Author(s):
- WANG Li-zhi; WANG Peng; XU Qiang; GENG Li-tao
-
Key Laboratory of University in Road and Traffic Engineering,
Shandong Jianzhu University
Jinan 250101, Shandong, China
- Keywords:
- road engineering; high modulus asphalt mixture; ; Fourier infrared spectroscopy; scanning electron microscope; gray level histogram; viscoelastic behavior
- PACS:
- U414.701
- DOI:
- -
- Abstract:
- High modulus asphalt mixtures have incurred a lot of attention because of great anti-rutting performance, especially additive-type high modulus asphalt mixtures. However, the effect of additive on the performance of asphalt mixture is still unknown. This paper investigated the mechanism of high modulus additives in the hot asphalt mixtures (HAM) by means of Fourier infrared spectrometer (FIR), asphalt extractor, scanning electron microscope (SEM) and dynamic shear rheometer (DSR). By analyzing the effect of additives on asphalt through FT IR functional group, the interaction between additives and asphalt mixtures, and the properties of asphalt mixtures, this paper investigated and compared the difference of asphalt viscoelastic behavior before and after adding high modulus additives and the properties of asphalt mixtures. The results show that esters with long fatty group carbon chain and polyolefin are useful constituents to improve low-temperature performance of hot asphalt mixtures. When mixing additive B melts and disperses in hot aggregate (180 ℃~190℃) by colliding and shearing, its aggregate surface after extraction has little residual additive because of smaller grain size and right melting point (about 150 ℃~160 ℃). So it makes more contribution than A. The SEM image shows that B is well-distributed in asphalt binder, displaying a centralized grey value in gray level histogram. DSR shows that asphalt binders which is added high modulus additives improves binder s viscoelastic behaviors, and obtains higher storage modulus G′, lower phase angle δ and higher viscosity. Few unmelted additives interlock into mixtures voids during compaction, which increases mixtures internal friction angle and asphalt mixtures modulus.
Last Update: 2015-11-23