Dynamic response and moisture stability improvement ofred mud asphalt mixture(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2021年5期
- Page:
- 11-22
- Research Field:
- 道路工程
- Publishing date:
Info
- Title:
- Dynamic response and moisture stability improvement ofred mud asphalt mixture
- Author(s):
- ZHANG Jizhe1; GUO Chenchen1; SU Chunhua2; LIANG Ming1; YAO Zhanyong
- (1. School of Qilu Transportation, Shandong University, Jinan 250002, Shandong, China;2. Shandong Transportation Research Institute, Jinan 250100, Shandong, China)
- Keywords:
- road engineering; red mud; asphalt mastic; asphalt mixture; moisture damage; durabilit
- PACS:
- -
- DOI:
- -
- Abstract:
- Aiming at the problem of insufficient water stability of asphalt mixture caused by water interface stripping of red mud asphalt mortar, lime and cement were selected to enhance and modify it. The effects of original red mud and modified red mud on rheological behavior and interfacial adhesion of asphalt mortar were studied by asphalt quality tester (QCT), PosiTest ATA, surface free energy tester, simple performance test system (SPT) and Hamburg rut tester (HWT). Based on the surface free energy, the adhesion and stripping energy of asphalt masticsaggregate interface were calculated. The thermodynamic evolution law of asphalt masticsaggregate interface was analyzed. The strength failure mechanism of asphalt masticsaggregate interface in red mud was revealed. And the dynamic response, high temperature rutting resistance and water stability of asphalt mixture were evaluated. The results show that red mud can improve the stiffness and elasticity of asphalt mastics. The asphalt mortar prepared by using red mud as filler alone has weak moisture damage resistance, while adding hydrated lime can obviously improve the bonding strength of red mud asphalt mastic, then improve the moisture stability of asphalt mastic. The thermodynamic adhesion of asphalt mastics to aggregate interface is consistent with the change of mechanical strength. The substitution of red mud for limestone powder resulted in the increase of dynamic modulus of asphalt mixture and the decrease of phase angle. The addition of hydrated lime further increases the dynamic modulus of asphalt mixture and reduces the phase angle. However, cement has limited influence on the dynamic modulus of red mud asphalt mixture. Red mud can improve the rutting resistance of asphalt mixture under dry condition, while adding content (mass fraction, the same below) 10% hydrated lime can further improve the rutting resistance of asphalt mixture. The substitution of red mud for limestone powder seriously affects the water damage resistance of asphalt mixture. The water damage resistance of red mud asphalt mixture can be improved by physical modification of red mud by hydrated lime. 10 tabs, 8 figs, 31 refs.
Last Update: 2021-09-30