Performance of composite modified asphalt by waste rubber powder and amorphous poly alpha olefin(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2018年02期
- Page:
- 1-8
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Performance of composite modified asphalt by waste rubber powder and amorphous poly alpha olefin
- Author(s):
- YAN Kezhen; CHEN Ming; HU Yue
- College of Civil Engineering， Hunan University， Changsha 410082， Hunan, China
- Keywords:
- road egineering; APAO; composite modified asphalt; preparation technique
- PACS:
- U414.1
- DOI:
- -
- Abstract:
- In order to study the influence of waste rubber powder (WTR) and amorphous poly alpha olefin (APAO) on composite modified asphalt and its optimum processing technology, multiple groups of blending quantity of WTR/APAO composite modified asphalt were prepared by using highspeed shearing method at first, then the penetration, softening point, viscosity and elastic recovery of WTR/APAO composite modified asphalt were measured, and simultaneously, the storage stability analysis and microscopic examination of fluorescence microscope were carried out. Finally, the optimum processing technology of WTR/APAO composite modified asphalt was determined by orthogonal test. The results show that when the blending quantity of waste rubber powder and APAO (mass fraction, the same below) is 15% and 4%, respectively, the penetration of WTR/APAO composite modified asphalt is lower than that of matrix asphalt by 36.8 mm, the softening point increases by 22.9 ℃, the elastic recovery increases by 67%, and the viscosity (180 ℃) increases by 81%. And all indexes meet the requirements of the evaluation index of rubber asphalt. This indicates that after adding appropriate amount of WTR and APAO, high temperature performance and recoverable deformation ability of matrix asphalt are significantly improved, and WTR/APAO composite modified asphalt has better modification effect. Moreover, compared to WTR modification alone, the addition of APAO can result in a further decrease in penetration and a further increase in softening point, viscosity and elastic recovery, the addition of APAO can further enhance the effect of WTR modification alone. The storage stability experiment reveals that the softening point difference of WTR/APAO composite modified asphalt decreases by 3.3 ℃ compared to waste rubber powder modified asphalt with the blending quantity of 15% alone after adding 4% APAO, which proves that the addition of APAO can significantly improve the storage stability of the waste rubber powder modified asphalt and can make up for the deficiency of waste rubber powder modified asphalt. Fluorescence microscopy experiments also show that APAO not only enhances the dispersion of WTR, but also improves the compatibility of WTR with asphalt. The basic parameters of the optimal processing technology for WTR/APAO composite modified asphalt are that WTR is added before APAO, and shear temperature 190 ℃, the sheared time 90 min, and shear rate 5 000 r/min. 6 tabs, 7 figs, 26 refs.
Last Update: 2018-04-03