Li Hui, Shi Miao, Zhang Jia, Peng Liangliang
Institute of Urban Rail Transit, Liaoning Railway Vocational and Technical College, Jinzhou, China.
School of Civil Engineering, Liaoning University of Technology, Jinzhou, China.
PLoS One. 2025 Jun 2;20(6):e0321058. doi: 10.1371/journal.pone.0321058. eCollection 2025.
Geotextile bag dams withstand the earth pressure of tailings in tailings reservoir by the shear stress on interface of geotextile bags. To improve the interfacial friction characteristics, pull-out tests were conducted on geotextile bags filled with fine tailings slurry containing various cement content, and the influences of cement content on the interfacial shear characteristics were explored. To describe the progressive failure of the interface, the theoretical analysis of interface pull-out behavior was performed. The results revealed that adding content cement into fine tailings slurry not only augmented the shear strength and residual strength ratio of the interface but also postponed interface softening. The optimal amount of cement was 3%, and the apparent friction angle which played a dominant role in interface strength was increased 17.4%, compared with no cement used. The elastic-plastic model and trilinear softening model were respectively improved to conform to the interfacial shear characteristics obtained in pull-out tests under low normal stress (< 60 kPa) and high normal stress (≥60 kPa). The interface shear stiffness of geotextile bag with the interfacial displacement within 20 mm and the dynamic compression modulus along the drawing direction were regarded as significant model parameters. The comparative analysis of shear stress-displacement curves, which were obtained from model calculating and test measuring, was carried out to verify the reliability and rationality of the model. The evolution patterns of the plastic zone, softening zone and residual zone of the interface were analyzed based on the model, and the warning values for interface failure were proposed. The development degree of interfacial plastic zone, softening zone and residual zone can be approximately calculated by quadratic polynomial of normalized pull-out force. The research results of this paper will provide reliable theoretical support for the design, construction and operation management of geotextile bag dams.
土工织物袋坝通过土工织物袋界面上的剪应力来承受尾矿库中尾矿的土压力。为了改善界面摩擦特性，对填充有含不同水泥含量的细尾矿浆的土工织物袋进行了拉拔试验，并探讨了水泥含量对界面剪切特性的影响。为了描述界面的渐进破坏，对界面拉拔行为进行了理论分析。结果表明，在细尾矿浆中添加水泥不仅提高了界面的抗剪强度和残余强度比，还延缓了界面软化。最佳水泥用量为3%，与不使用水泥相比，对界面强度起主导作用的表观摩擦角增加了17.4%。分别改进了弹塑性模型和三线软化模型，以符合在低法向应力（<60 kPa）和高法向应力（≥60 kPa）下的拉拔试验中获得的界面剪切特性。将土工织物袋在界面位移20 mm内的界面剪切刚度和沿拉伸方向的动态压缩模量视为重要的模型参数。通过对模型计算和试验测量得到的剪应力-位移曲线进行对比分析，验证了模型的可靠性和合理性。基于该模型分析了界面塑性区、软化区和残余区的演化模式，并提出了界面破坏的预警值。界面塑性区、软化区和残余区的发展程度可以通过归一化拉拔力的二次多项式近似计算。本文的研究成果将为土工织物袋坝的设计、施工和运行管理提供可靠的理论支持。
