长江科学院院报 ›› 2022, Vol. 39 ›› Issue (5): 95-98.DOI: 10.11988/ckyyb.20210294

• 岩土工程 • 上一篇    下一篇

干湿循环作用下铁尾矿砂水泥土强度劣化规律

胡建林1,2, 高鹏飞1, 崔宏环1,2, 张玉龙1   

  1. 1.河北建筑工程学院 土木工程学院,河北 张家口 075000;
    2.河北省土木工程诊断、改造与抗灾重点实验室,河北 张家口 075000
  • 收稿日期:2021-03-31 修回日期:2021-06-09 出版日期:2022-05-01 发布日期:2022-05-17
  • 通讯作者: 高鹏飞(1997-),男,内蒙古乌海人,硕士研究生,研究方向为地基处理。E-mail:819211266@qq.com
  • 作者简介:胡建林(1986-),男,河北张家口人,副教授,硕士,研究方向为地基处理。E-mail:hjl185@126.com
  • 基金资助:
    国家自然科学基金项目(51878242);河北省教育厅重点资助项目 (ZD2020325);张家口市科技计划财政资助项目(1911035A)

Experimental Study on Strength Deterioration Law of Cement Soil Mixed with Iron Ore Tailings under Wetting-Drying Cycles

HU Jian-lin1,2, GAO Peng-fei1, CUI Hong-huan1,2, ZHANG Yu-long1   

  1. 1. School of Civil Engineering, Hebei Universityof Architecture, Zhangjiakou 075000, China;
    2. Key Laboratory of Civil Engineering Diagnosis, Reconstruction and Disaster Resistance of Hebei Province, Zhangjiakou 075000, China
  • Received:2021-03-31 Revised:2021-06-09 Online:2022-05-01 Published:2022-05-17

摘要: 为了探讨铁尾矿砂水泥土的力学性能及抗干湿循环劣化能力,通过无侧限抗压强度试验和干湿循环试验,研究水泥掺量、铁尾矿砂掺量及干湿循环次数对铁尾矿砂水泥土强度的影响。试验结果表明:铁尾矿砂在20%掺量下对水泥土的强度提升最大,在40%掺量下对水泥土的强度提升最小,最高强度增长率约为70%;干湿循环对素水泥土和铁尾矿砂水泥土的强度造成的损伤程度不同,素水泥土在循环初期强度损失较大而在循环后期损失较小且逐渐趋于平缓,铁尾矿砂水泥土在循环初期强度损失较小,超过一定循环次数后强度下降明显;水泥土强度劣化的主要原因是孔隙水的干缩湿涨造成水泥土内部的应力集中。

关键词: 力学特性, 铁尾矿砂, 水泥土, 干湿循环, 强度损失

Abstract: In order to explore the mechanical properties and anti-deterioration ability of iron tailings cement soil, we conducted unconfined compressive strength test and wetting-drying cycle test to examine the influences of cement content, iron tailing sand content and number of drying and wetting cycles on the strength of iron tailings cement soil. Results demonstrated that a dosage of 20% iron tailing sand had a largest improvement effect on the strength of cement soil, improving by about 70%; a dosage of 40% iron tailing sand had a least enhancement effect. Dry-wet cycles had deterioration effects of varied levels on the strengths of plain cement soil and iron tailings cement soil: the strength loss of plain soil-cement was greater at the initial stage of cycle than that in the later stage and tended to be gentle gradually, while the strength loss of iron tailings cement-soil was small at the initial stage of cycle, and the strength deteriorated obviously after a certain number of cycles. The main reason for the deterioration of cement-soil strength is the stress concentration caused by the drying shrinkage and wetting swelling of pores.

Key words: mechanical properties, tailings of iron ore, cement-soil, wetting-drying cycles, strength loss

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