Consolidation behavior and shear strength characteristics of polymer-paste tailings barrier

IF 4.1 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Physics and Chemistry of the Earth Pub Date : 2025-08-25 DOI:10.1016/j.pce.2025.104053

Chinaza C. Paul, Mamadou Fall

{"title":"Consolidation behavior and shear strength characteristics of polymer-paste tailings barrier","authors":"Chinaza C. Paul, Mamadou Fall","doi":"10.1016/j.pce.2025.104053","DOIUrl":null,"url":null,"abstract":"<div><div>Waste containment facilities, such as landfills and tailings storage facilities, rely on barrier (liner, cover) materials to prevent hazardous contaminant migration. Recently, polymer-enhanced paste tailings (PP) barriers, made from a compacted mixture of paste tailings and superabsorbent polymer (SAP), have emerged as a promising solution for sustainable waste containment due to their low permeability. However, although compacted PP shows promising hydraulic properties, its mechanical characteristics relevant to barrier functionality, such as consolidation behavior and shear characteristics, are not yet understood. No studies have assessed these mechanical characteristics. This study investigates the consolidation behavior and shear strength characteristics of polymer-paste tailings (PP) barriers incorporating superabsorbent polymers (SAPs). Compacted PP samples with different concentrations of SAP (0.0 %, 0.2 %, 0.5 %) were prepared, and the samples were subjected to consolidation and shear tests. Consolidation behavior was investigated using oedometer tests, monitoring settlement over time under different stress conditions. In addition, shear characteristics were assessed by direct shear tests to evaluate the material's resistance to shearing and deformation under different normal stresses. The results indicated that increasing SAP content accelerates the consolidation process. In contrast, the shear strength of the material increases with SAP content up to 0.2 %, after which it decreases when the SAP content reaches 0.5 %. This means that the shear strength of the compacted PP is strongly dependent on the amount of SAP concentration. Specifically, the cohesion increases with higher SAP content, whereas the friction angle decreases with increasing SAP content. These findings highlight the importance of balancing SAP content to achieve a stable and efficient barrier system. The findings position this PP material as an attractive option for barrier design, offering the benefits of minimizing waste management and lowering the expenses associated with tailings management at the earth's surface.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"141 ","pages":"Article 104053"},"PeriodicalIF":4.1000,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics and Chemistry of the Earth","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1474706525002037","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

Waste containment facilities, such as landfills and tailings storage facilities, rely on barrier (liner, cover) materials to prevent hazardous contaminant migration. Recently, polymer-enhanced paste tailings (PP) barriers, made from a compacted mixture of paste tailings and superabsorbent polymer (SAP), have emerged as a promising solution for sustainable waste containment due to their low permeability. However, although compacted PP shows promising hydraulic properties, its mechanical characteristics relevant to barrier functionality, such as consolidation behavior and shear characteristics, are not yet understood. No studies have assessed these mechanical characteristics. This study investigates the consolidation behavior and shear strength characteristics of polymer-paste tailings (PP) barriers incorporating superabsorbent polymers (SAPs). Compacted PP samples with different concentrations of SAP (0.0 %, 0.2 %, 0.5 %) were prepared, and the samples were subjected to consolidation and shear tests. Consolidation behavior was investigated using oedometer tests, monitoring settlement over time under different stress conditions. In addition, shear characteristics were assessed by direct shear tests to evaluate the material's resistance to shearing and deformation under different normal stresses. The results indicated that increasing SAP content accelerates the consolidation process. In contrast, the shear strength of the material increases with SAP content up to 0.2 %, after which it decreases when the SAP content reaches 0.5 %. This means that the shear strength of the compacted PP is strongly dependent on the amount of SAP concentration. Specifically, the cohesion increases with higher SAP content, whereas the friction angle decreases with increasing SAP content. These findings highlight the importance of balancing SAP content to achieve a stable and efficient barrier system. The findings position this PP material as an attractive option for barrier design, offering the benefits of minimizing waste management and lowering the expenses associated with tailings management at the earth's surface.

查看原文本刊更多论文

聚合物-膏体尾砂屏障固结特性及抗剪强度特性

废物控制设施，如垃圾填埋场和尾矿储存设施，依靠屏障（衬垫、覆盖物）材料来防止有害污染物的迁移。最近，聚合物增强膏体尾矿（PP）屏障，由膏体尾矿和高吸水性聚合物（SAP）的压实混合物制成，由于其低渗透性，已成为一种有前途的可持续废物遏制解决方案。然而，尽管压实PP表现出良好的水力性能，但其与屏障功能相关的力学特性，如固结行为和剪切特性，尚不清楚。没有研究评估过这些机械特性。本研究研究了含高吸水性聚合物（sap）的聚合物-膏体尾矿（PP）屏障的固结行为和抗剪强度特性。制备了不同SAP浓度（0.0%、0.2%、0.5%）的PP压实样品，并对样品进行了固结和剪切试验。固结行为的研究采用了里程表试验，监测不同应力条件下随时间的沉降。此外，通过直剪试验评估了材料的剪切特性，以评估材料在不同法向应力下的剪切和变形抗力。结果表明，SAP含量的增加加速了固结过程。当SAP含量达到0.2%时，材料的抗剪强度增大，当SAP含量达到0.5%时，材料的抗剪强度减小。这意味着压实PP的抗剪强度很大程度上取决于SAP的浓度。粘聚力随SAP含量的增加而增加，摩擦角随SAP含量的增加而减小。这些发现突出了平衡SAP含量以实现稳定有效屏障系统的重要性。研究结果表明，这种PP材料作为屏障设计的一个有吸引力的选择，提供了最大限度地减少废物管理和降低与地球表面尾矿管理相关的费用的好处。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Physics and Chemistry of the Earth 地学-地球科学综合

CiteScore

5.40

自引率

2.70%

发文量

176

审稿时长

31.6 weeks

期刊介绍： Physics and Chemistry of the Earth is an international interdisciplinary journal for the rapid publication of collections of refereed communications in separate thematic issues, either stemming from scientific meetings, or, especially compiled for the occasion. There is no restriction on the length of articles published in the journal. Physics and Chemistry of the Earth incorporates the separate Parts A, B and C which existed until the end of 2001. Please note: the Editors are unable to consider submissions that are not invited or linked to a thematic issue. Please do not submit unsolicited papers. The journal covers the following subject areas: -Solid Earth and Geodesy: (geology, geochemistry, tectonophysics, seismology, volcanology, palaeomagnetism and rock magnetism, electromagnetism and potential fields, marine and environmental geosciences as well as geodesy). -Hydrology, Oceans and Atmosphere: (hydrology and water resources research, engineering and management, oceanography and oceanic chemistry, shelf, sea, lake and river sciences, meteorology and atmospheric sciences incl. chemistry as well as climatology and glaciology). -Solar-Terrestrial and Planetary Science: (solar, heliospheric and solar-planetary sciences, geology, geophysics and atmospheric sciences of planets, satellites and small bodies as well as cosmochemistry and exobiology).