Yang Yonghao, Huang Feng, Wei Zuoan, Wang Yanlei, Lu Ting, Zheng Binbin, Xia Jiang
State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing, 400074, China.
School of Civil Engineering, Chongqing Jiaotong University, Chongqing, 400074, China.
Environ Sci Pollut Res Int. 2023 Apr;30(16):47274-47288. doi: 10.1007/s11356-023-25680-8. Epub 2023 Feb 4.
Earthquakes are a significant factor that contributes to tailings dam failure. Generally, the seismic stability of a tailings dam can be increased by improving the dynamic properties of tailings. The dynamic properties of tailings can be improved effectively using polymers. In this study, the dynamic properties of polyacrylamide-reinforced tailings were investigated via a sequence of dynamic triaxial tests. The content of polyacrylamide in the test sample was 0.3%. Test results show that the cyclic liquefaction resistance, initial dynamic shear modulus, dynamic shear modulus, and dynamic shear modulus ratio of polyacrylamide-reinforced tailings were slightly greater than those of unreinforced tailings. The damping ratio of polyacrylamide-reinforced tailings was lower than that of unreinforced tailings when the dynamic shear strain exceeded 0.038%. The increase in the dynamic pore water pressure of polyacrylamide-reinforced tailings during cyclic loading decelerated significantly compared with that of unreinforced tailings. The revised Zeng model can effectively described the changes in dynamic pore-water pressure of unreinforced and polyacrylamide-reinforced tailings. The polyacrylamide can improve the structural stability of the tailings specimen and also improve the dynamic properties of the tailings, thereby enhancing the seismic stability of the tailings dam.
地震是导致尾矿坝失效的一个重要因素。一般来说，通过改善尾矿的动力特性可以提高尾矿坝的抗震稳定性。使用聚合物可以有效地改善尾矿的动力特性。在本研究中，通过一系列动三轴试验研究了聚丙烯酰胺增强尾矿的动力特性。试验样品中聚丙烯酰胺的含量为0.3%。试验结果表明，聚丙烯酰胺增强尾矿的抗循环液化能力、初始动剪切模量、动剪切模量和动剪切模量比略大于未增强尾矿。当动剪应变超过0.038%时，聚丙烯酰胺增强尾矿的阻尼比低于未增强尾矿。与未增强尾矿相比，聚丙烯酰胺增强尾矿在循环加载过程中动孔隙水压力的增加显著减缓。修正后的曾模型可以有效地描述未增强和聚丙烯酰胺增强尾矿动孔隙水压力的变化。聚丙烯酰胺可以提高尾矿试样的结构稳定性，还可以改善尾矿的动力特性，从而提高尾矿坝的抗震稳定性。
