赤泥复合固化剂固化粉土路用性能及其机理
作者:
作者单位:

1.上海公路桥梁(集团)有限公司, 上海 200433;2.中国矿业大学 土木工程灾变与智能防控省高校重点实验室,江苏 徐州 221116

作者简介:

吴伟军(1973—),男,上海人,上海公路桥梁(集团)有限公司高级工程师,工学硕士.E-mail:zn01142023@163.com

通讯作者:

张鲲鹏(1983—),男,上海人,上海公路桥梁(集团)有限公司高级工程师,工学硕士.E-mail:57494757@qq.com

中图分类号:

U416.1

基金项目:

”十四五”国家重点研发计划项目(2023YFC2907301)


Road Performance of Red Mud Composite Solidification Agent for Solidified Silt and Its Mechanism
Author:
Affiliation:

1.Shanghai Road and Bridge( Group) Co. Ltd., Shanghai 200433,China;2.Jiangsu Key Laboratory of Disaster Impact and Intelligent Prevention in Civil Engineering, China University of Mining and Technology,Xuzhou 221116,China

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • | |
  • 文章评论
    摘要:

    利用工业废弃物赤泥、电石渣和脱硫石膏组成的赤泥复合固化剂对低液限粉土进行固化,探究了固化粉土的力学性能(无侧限抗压强度和劈裂强度)和耐久性(水稳定性和干湿循环),并采用扫描电镜(SEM)和X射线衍射仪(XRD)分析赤泥复合固化剂的固化机理.结果表明:固化粉土的无侧限抗压强度和劈裂强度随着赤泥复合固化剂掺量的增加和养护龄期的延长而提高;当赤泥复合固化剂掺量由8%增至24%且养护龄期由7 d延至28 d时,固化粉土的水稳系数由69.5%提高到82.4%;干湿循环12次后,固化粉土的强度损失率为35.14%.赤泥复合固化剂掺入粉土中发生水化反应,生成具有胶凝作用的水化硅酸钙(C-S-H)和水化铝酸钙(C-A-H)凝胶,同时C-A-H与CaSO4生成钙矾石(AFt)晶体;C-S-H和C-A-H包裹并填充着土颗粒,AFt晶体穿插在土颗粒间,使其成为一个整体,有效提高了固化粉土的路用性能.

    Abstract:

    Red mud composite stabilizers, composed of industrial wastes such as red mud, carbide slag, and desulfurized gypsum, were used to solidify low liquid limit silt. The changes in mechanical properties (unconfined compressive strength and splitting strength) and durability (water stability and dry-wet cycle) of the solidified silt were explored. Additionally, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to analyze the solidification mechanism of red mud composite solidification agent. The results show that the unconfined compressive strength and splitting strength of solidified silt increase with both the increasing content of the stabilizer and the extension of curing age. When the content of red mud composite solidification agent is increased from 8% to 24% and the age of maintenance is extended from 7 d to 28 d. The water stability coefficient improves from 69.5% to 82.4%. After 12 dry-wet cycles, the strength loss rate of stabilized silt reaches 35.14%. When the red mud composite stabilizer is incorporated into the silt, hydration reactions occur, forming gelatinous calcium silicate hydrate (C-S-H) and calcium aluminate hydrate (C-A-H) gels. Simultaneously, C-A-H reacts with CaSO4 to produce ettringite (AFt) crystals. The C-S-H and C-A-H gels encapsulate and fill the soil particles, while the AFt crystals interpenetrate the soil particles, integrating them into a whole and effectively enhancing the road performance of solidified silt.

    图1 3种固化剂的XRD图谱Fig.1 XRD patterns of three kinds of solidification agents
    图2 固化粉土无侧限抗压强度随赤泥复合固化剂掺量和养护龄期的变化Fig.2 Variation of unconfined compressive strength of solidified silts with red mud composite solidification agent content and curing age
    图3 固化粉土劈裂强度随赤泥复合固化剂掺量和养护龄期的变化Fig.3 Variation of splitting strength of solidified silts with red mud composite solidification agent content and curing age
    图4 固化粉土水稳系数随赤泥复合固化剂掺量和养护龄期的变化Fig.4 Variation of water stability coefficient of solidified silts with red mud solidification agent content and curing age
    图5 固化粉土(赤泥复合固化剂掺量为16%)质量损失率和体积膨胀率随干湿循环次数的变化Fig.5 Variation of mass loss rate and volume expansion rate of solidified silts(red mud solidification agent content is 16% ) with number of dry-wet cycle
    图6 固化粉土(赤泥复合固化剂掺量为16%)无侧限抗压强度随干湿循环次数的变化Fig.6 Variation of unconfined compressive strength of solidified silts(red mud solidification agent content is 16% ) with number of dry-wet cycle
    图7 3种典型试样的XRD图谱Fig.7 XRD patterns of three kinds of typical samples
    图8 3种典型试样的SEM照片Fig.8 SEM images of three kinds of typical samples
    表 1 土样的基本物理指标Table 1 Basic physical indicators of silt sample
    表 2 3种固化剂的化学组成Table 2 Chemical compositions(by mass) of three kinds of solidification agents
    表 3 固化粉土微观试验方案Table 3 Microscopic test scheme for solidified silts
    参考文献
    相似文献
    引证文献
引用本文

吴伟军,张鲲鹏,张宁,丁北斗,王佳辉.赤泥复合固化剂固化粉土路用性能及其机理[J].建筑材料学报,2025,28(3):227-235

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2024-04-12
  • 最后修改日期:2024-07-25
  • 在线发布日期: 2025-04-06
文章二维码