Creep characteristics and microstructure analysis of graphene/rubber
powder composite modified asphalt based on aging
(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年1期
- Page:
- 97-106
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Creep characteristics and microstructure analysis of graphene/rubber
powder composite modified asphalt based on aging
- Author(s):
- WU Hongjuan1; WANG Xuancang2; WANG Rui1; ZHANG Wei1; CHEN Chengqin1
- 1. College of Civil Engineering, Northwest Minzu University, Lanzhou 730010, Gansu, China; 2. School of Highway, Changan University, Xian 710064, Shaanxi, China
- Keywords:
- road engineering; creep; Burgers model; graphene/rubber powder composite modified asphalt; microstructure
- PACS:
- -
- DOI:
- -
- Abstract:
- To analyze the influence of graphene content and aging on creeprecovery performance, creep parameters and the relative proportion of elastic deformation, delayed elastic deformation, and irrecoverable viscous deformation. Crumb rubber asphalt with different graphene contents were prepared and subjected to a rolling thinfilm oven test (RTFOT) and pressure aging vessel (PAV) aging. Repeated creeprecovery tests of 60 °C were applied to the specimen. First, based on the Burgers model, the creep parameters of each asphalt sample were determined. To reduce the fitting error of the Burgers model, the estimation of the instantaneous elastic modulus of the Burgers model was dependent on the relationship between the creep compliance and time. Then, proportions of different deformations for asphalt at different aging stages were calculated and the influence of graphene content on the deformation proportions was analyzed. Finally, scanning electron microscopy (SEM) was performed to observe the microstructure of the rubber asphalt and graphene/rubber asphalt at different degrees of aging. The results show that the RTFOT rubber asphalt presents the greatest creep followed by the PAV asphalt and original rubber asphalt, the effect of aging on rubber asphalt creep is reduced by increasing graphene content, and RTFOT leads to a significant decrease of the delayed elastic deformation proportion. However, its proportion increases to a certain extent after PAV. In addition, the SEM shows that the original rubber asphalt exhibits obvious heterogeneity and the identifiable rubber particles decrease and present a swelling state after aging. The microstructure of the original graphene/rubber asphalt is similar to that of rubber asphalt. However, a large area of agglomerates appears in the graphene/rubber asphalt after aging.
4 tabs, 13 figs, 21 refs.
Last Update: 2020-01-17