Details

Autor(en) / Beteiligte

• Wang, Xiao-lin
• Wang, Hong-jiang
• Wu, Ai-xiang
• Jiang, Hai-qiang
• Peng, Qing-song
• Zhang, Xi

Titel

Evaluation of time-dependent rheological properties of cemented paste backfill incorporating superplasticizer with special focus on thixotropy and static yield stress

Ist Teil von

• Journal of Central South University, 2022-04, Vol.29 (4), p.1239-1249

Ort / Verlag

Changsha: Central South University

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Superplasticizers are widely used to reduce the pipe flow resistance of cemented paste backfill (CPB), which is characterised by high concentration and high yield stress. This study aimed to assess the time-dependent rheological properties of CPB containing superplasticizer, with special focus on static yield stress and thixotropy. The results indicate that with the increase of the superplasticizer dosage, the static yield stress, dynamic yield stress and thixotropy of CPB decreased significantly, while the plastic viscosity decreased slightly. The curing time has a significant effect on the static yield stress, dynamic yield stress and thixotropy of CPB containing superplasticizer, which increase by 46.6%–87.1%, 15.2%–35.6% and 79.4%–138.2%, respectively, within 2 h. The static yield stress, dynamic yield stress and thixotropy of CPB without superplasticizer only increase by 4.9%, 6.3% and 16.1%, respectively, within 2 h. The curing time has a significant influence on the plastic viscosity of CPB regardless of superplasticizer addition, the plastic viscosity increases by 13.2%–19.7% within 2 h. Regardless of superplasticizer dosage, plotting of both static yield stress and dynamic yield stress versus thixotropy produces clearly linear curves. The findings of this study are conducive to the design of pipe transportation of CPB containing superplasticizer.