基于膏體穩定系數的級配表征及屈服應力預測

程海勇; 吳順川; 吳愛祥; 程緯華

doi:10.13374/j.issn2095-9389.2018.10.003

基于膏體穩定系數的級配表征及屈服應力預測

doi: 10.13374/j.issn2095-9389.2018.10.003

程海勇^1,2,
吳順川^1,2, ,,
吳愛祥²,
程緯華¹

1) 昆明理工大學國土資源工程學院, 昆明 650093;
2) 金屬礦山高效開采與安全教育部重點實驗室, 北京 100083

基金項目:

金屬礦山高效開采與安全教育部重點實驗室開放基金資助項目(ustbmslab201801)

國家自然科學基金資助項目(51574013)

詳細信息

中圖分類號: TD853
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出版歷程
- 收稿日期: 2017-11-30

Grading characterization and yield stress prediction based on paste stability coefficient

1) Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China;
2) Key Laboratory of Ministry of Education of China for Efficient Mining and Safety of Metal Mines, Beijing 100083, China

摘要

摘要: 由于不同礦山充填材料性質千差萬別,屈服應力影響因素很難統一分析.通過多個礦山尾砂試樣,依次開展了級配表征及影響實驗、相似密度流變實驗以及基于體積分數和灰砂比的雙因素流變實驗,并結合細觀圖像分析技術,實現了屈服應力演化機理的研究.研究表明:膏體穩定系數是級配的有效表征方式,能夠表現散體和流體綜合特征;屈服應力隨膏體穩定系數呈冪指數增長,隨濃度呈指數型增長,隨密度呈負指數增長,由此構建的全尾砂膏體屈服應力預測模型誤差在10%以內;細觀圖像分析認為屈服應力主要受級配結構和絮網結構支配,級配結構構成了料漿可塑性和穩定性的基礎,絮網結構將自由水轉變為半穩定形態的吸附水,引起屈服應力宏觀演化.
- 膏體充填 /
- 屈服應力 /
- 流變 /
- 級配 /
- 穩定系數
Abstract: Paste backfilling has become an important support technology in green mining construction. The flowability and rheology performance of paste determine whether the slurry can be transported normally. As such, the evaluation of flowability and rheology of paste are important factors in the reliability of paste transportation. Because paste has the three characteristics of fluidity, stability and plasticity, traditional two-phase flow theory cannot effectively analyze its plug flow. However, it is an effective method for analyzing and evaluating the fluidity of the paste based on rheology theory, and the yield stress is an important parameter for evaluating the rheological characteristics of paste. Due to the different properties of the materials in different mines, it is difficult to analyze the factors that influence yield stress. Several experiments have been conducted on a variety of tailings from different mines, including a gradation characterization and influence experiment, a rheology experiment on materials of similar densities, and double-factor rheological experiments based on the concentration and sand ratio. Combined with mesoscopic structure analysis technology, the evolution mechanism of yield stress was studied. The results indicate that the stability coefficient of paste can effectively reflect the gradation, and can also reflect the comprehensive characteristics of the granule and fluid. The yield stress increases significantly with the paste stability coefficient and increases exponentially with the concentration. At the same time, yield stress is characterized by negative exponential growth with density. The error range of this yield stress prediction model for unclassified tailings paste is within 10%. The mesoscopic structure analysis shows that yield stress is mainly controlled by gradation and flocculent structure. The gradation constitutes the foundation for the plasticity and stability of the slurry. The flocculent structure transforms free water into the semi-stable form of adsorptive water, which causes the macro-evolution of the yield stress.
- paste backfill /
- yield stress /
- rheology /
- gradation /
- stability coefficient

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參考文獻(4)

[1]	Nehdi M, Rahman M A. Estimating rheological properties of cement pastes using various rheological models for different test geometry, gap and surface friction. Cem Concr Res, 2004, 34(11):1993
[2]	He M Z, Wang Y M, Forssberg E. Slurry rheology in wet ultrafine grinding of industrial minerals:a review. Powder Technol, 2004, 147(1-3):94
[14]	Ke X, Hou H B, Zhou M, et al. Effect of particle gradation on properties of fresh and hardened cemented paste backfill. Constr Build Mater, 2015, 96:378
[16]	Zhang J B, An X H, Nie D. Effect of fine aggregate characteristics on the thresholds of self-compacting paste rheological properties. Constr Build Mater, 2016, 116:355