Rheological properties of cemented coal gangue backfill based on response surface methodology

• Published in: Construction & building materials 2021-11, Vol.306, p.124836, Article 124836
• Main Authors: Zhu, Lingli, Jin, Zhenghao, Zhao, Yu, Duan, Yihang
• Format: Article
• Language: English
• Subjects: Cemented coal gangue backfill; Gangue; Regression model; Response surface methodology; Rheological properties
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2021.124836

•The method of analyzing rheological parameters by Box-Behnken Design was established.•The rheological properties of cemented coal gangue backfill was studied.•The regression models of rheological parameters were established.•The weight of effect factors on rheological parameters was characterized. In order to study the different mix proportions on rheological properties of cemented coal gangue backfill (CGB). Firstly, by single-factor test, the appropriate dosage ranges of mass concentration, fly ash content and fine gangue ratio were determined. Then on this basis, by response surface methodology, the quadratic polynomial regression models of yield stress and plastic viscosity were constructed respectively. The results show that the rheological model of fresh CGB accorded with rheological behavior of the Bingham fluid. With the increase of mass concentration, the yield stress of fresh CGB increases significantly. With the increase of fly ash content, the plastic viscosity of fresh CGB increase significantly. With the increase of the fine gangue ratio, the yield stress of fresh CGB decreases first and then increases, and the plastic viscosity increases slowly. This study will provide theoretical support for practitioners to predict the rheological properties of fresh CGB with different material compositions, and optimize the pumping performance in order to guide the engineering application more accurately.