Yang Liu, An Lingshi, Yan Kuangyu, Du Gaofeng
Hunan Mine Carbon Sequestration and Sink Enhancement Engineering Technology Research Center, Changsha 410151, China.
Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Central South University, Ministry of Education, Changsha 410083, China.
Polymers (Basel). 2024 Dec 16;16(24):3500. doi: 10.3390/polym16243500.
As is widely accepted, cumulative strain and improvement mechanisms of stabilized soil are critical factors for the long-term reliable operation of expressways and high-speed railways. Based on relevant research findings, xanthan gum biopolymer is regarded as a green and environmentally friendly curing agent in comparison to traditional stabilizers, such as cement, lime, and fly ash. However, little attention has been devoted to the cumulative strain and improvement mechanisms of soil reinforced by xanthan gum biopolymer under traffic loading. In the current study, a series of laboratory tests, including cyclic triaxial tests and scanning electron microscopy (SEM) tests, were performed to investigate this issue in more detail. The influences of xanthan gum biopolymer content, curing time, moisture content, confining pressure, and cyclic stress amplitude on cumulative strain were analyzed. In addition, the cumulative strain model was proposed to provide a good description of experimental data. Finally, the microscopic structure of soil reinforced by xanthan gum biopolymer was analyzed to discuss the improvement mechanisms. The results show that the cumulative strain is strongly influenced by xanthan gum biopolymer content. For a given number of loading cycles, the greater the confining pressure, the smaller the cumulative strain. The calculated results of the cumulative strain model show a good agreement with test data. The "flocculent" hydrogel can form a denser structure and greater bonding strength in comparison to the "branch-like" and "net-like" hydrogels.
众所周知，稳定土的累积应变和改良机理是高速公路和高速铁路长期可靠运营的关键因素。基于相关研究成果，与水泥、石灰和粉煤灰等传统稳定剂相比，黄原胶生物聚合物被视为一种绿色环保的固化剂。然而，对于交通荷载作用下黄原胶生物聚合物加固土的累积应变和改良机理关注较少。在本研究中，进行了一系列室内试验，包括循环三轴试验和扫描电子显微镜（SEM）试验，以更详细地研究这一问题。分析了黄原胶生物聚合物含量、养护时间、含水量、围压和循环应力幅值对累积应变的影响。此外，提出了累积应变模型以很好地描述试验数据。最后，分析了黄原胶生物聚合物加固土的微观结构以探讨改良机理。结果表明，累积应变受黄原胶生物聚合物含量的强烈影响。对于给定的加载循环次数，围压越大，累积应变越小。累积应变模型的计算结果与试验数据吻合良好。与“树枝状”和“网状”水凝胶相比，“絮凝状”水凝胶能形成更致密的结构和更大的粘结强度。
