原料土液限对自密实固化土工程性质的影响

doi:10.16552/j.cnki.issn1001-1625.2024.0769

摘要/Abstract

摘要： 自密实固化土凭借就地取土、协同处置建筑垃圾、自流平、易泵送的优点在多种回填工程中得到了广泛应用。本文通过流动度试验、泌水率试验、湿密度试验、干缩试验和无侧限抗压强度试验,探究了原料土液限对自密实固化土性质的影响,并借助自由水分离试验探讨了自由水含量对强度特征的作用机理。结果表明:在相同水泥掺量和掺水率条件下,以高液限黏土为原料土制成的自密实固化土新拌浆体流动度较低,固化后无侧限抗压强度较高;随着掺水率的增加,新拌浆体的流动度增长幅度基本保持不变,固化后的无侧限抗压强度降低幅度开始减少;任意龄期条件下,以高液限黏土为原料土制成的自密实固化土中自由水含量均较低。在7 d养护龄期时,以高液限黏土为原料土制成的自密实固化土中自由水含量仅为2.2%,而低液限黏土自密实固化土试样的自由水含量为11.7%。该研究成果揭示了不同原料土液限对自密实固化土中自由水含量的影响机制,可为工程实践中原料土的选择及其配比设计提供指导。

关键词: 自密实固化土, 液限, 自由水, 流动度, 无侧限抗压强度

Abstract: Self-compacting solidified soil has been extensively utilized in various backfilling projects due to its advantages such as on-site soil extraction, synergistic disposal of construction waste, self-leveling, and pumpability. This study investigated the influence of liquid limit of raw soil on the engineering properties of self-compacting solidified soil through a series of tests including fluidity, bleeding rate, wet density, drying shrinkage, and unconfined compressive strength tests, complemented by free water separation tests to further explore the role of free water content in strength characteristics. The results demonstrate that under identical cement content and water-to-soil ratio, the freshly mixed slurry of self-compacting solidified soil made from high liquid limit clay exhibits lower fluidity but higher unconfined compressive strength after curing. With an increase in the water-to-soil ratio, the increment in fluidity of the freshly mixed slurry remains relatively constant, while the reduction in unconfined compressive strength after curing begins to diminish. Regardless of the curing age, the content of free water in self-compacting solidified soil made from high liquid limit clay is consistently lower. At a curing age of 7 d, the free water content in self-compacting solidified soil made from high liquid limit clay is only 2.2%, compared to 11.7% in samples made from low liquid limit clay. This research unveils the mechanism by which different liquid limits of raw soil affect the free water content in self-compacting solidified soil, offering scientific guidance for the selection of raw soil and the design of its mix proportion in engineering applications.

Key words: self-compacting solidified soil, liquid limit, free water, fluidity, unconfined compressive strength

中图分类号:

TU477

徐婕, 梁剑辉, 齐乐, 龚英, 高玉峰. 原料土液限对自密实固化土工程性质的影响[J]. 硅酸盐通报, 2025, 44(1): 360-367.

XU Jie, LIANG Jianhui, QI Le, GONG Ying, GAO Yufeng. Influence of Raw Soil Liquid Limit on Engineering Properties of Self-Compacting Solidified Soil[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2025, 44(1): 360-367.

参考文献

[1] 朱伟, 张春雷, 刘汉龙, 等. 疏浚泥处理再生资源技术的现状[J]. 环境科学与技术, 2002, 25(4): 39-41+50.
ZHU W, ZHANG C L, LIU H L, et al. The status quo of dredged spoils utilization[J]. Environmental Science and Technology, 2002, 25(4): 39-41+50 (in Chinese).
[2] 周永祥, 霍孟浩, 侯莉, 等. 低强度流态填筑材料的研究现状及展望[J]. 材料导报, 2024, 38(15): 130-138.
ZHOU Y X, HUO M H, HOU L, et al. Current research and prospect of low strength flowable filling materials[J]. Materials Reports, 2024, 38(15): 130-138 (in Chinese).
[3] 李丽华, 韩琦培, 杨星, 等. 稻壳灰-水泥固化淤泥土力学特性及微观机理研究[J]. 土木工程学报, 2023, 56(12): 166-176.
LI L H, HAN Q P, YANG X, et al. Mechanical properties and micro-mechanisms of RHA-cement solidified sludge[J]. China Civil Engineering Journal, 2023, 56(12): 166-176 (in Chinese).
[4] BAYESTEH H, HEZAREH H. Behavior of cement-stabilized marine clay and pure clay minerals exposed to high salinity grout[J]. Construction and Building Materials, 2023, 383: 131334.
[5] 邓永锋, 吴子龙, 刘松玉, 等. 地聚合物对水泥固化土强度的影响及其机理分析[J]. 岩土工程学报, 2016, 38(3): 446-453.
DENG Y F, WU Z L, LIU S Y, et al. Influence of geopolymer on strength of cement-stabilized soils and its mechanism[J]. Chinese Journal of Geotechnical Engineering, 2016, 38(3): 446-453 (in Chinese).
[6] 郎瑞卿, 裴璐熹, 孙立强, 等. 新拌不同液限淤泥固化土流动性试验研究[J]. 岩土力学, 2023, 44(10): 2789-2797.
LANG R Q, PEI L X, SUN L Q, et al. Experimental study on the flowability of freshly mixed solidified muds with different liquid limits[J]. Rock and Soil Mechanics, 2023, 44(10): 2789-2797 (in Chinese).
[7] 王文军, 袁飞飞, 蒋建良, 等. 高含水率吹填淤泥固化土强度特性及预测模型[J]. 地下空间与工程学报, 2021, 17(2): 461-467.
WANG W J, YUAN F F, JIANG J L, et al. Strength properties and prediction models of solidified dredger filled mud with high water-content[J]. Chinese Journal of Underground Space and Engineering, 2021, 17(2): 461-467 (in Chinese).
[8] 邵吉成, 李送根, 张旺兴, 等. 淤泥初始含水率及压实度对固化土强度的影响[J/OL]. 土木工程学报, 1-13 (2023-12-08)[2024-08-02]. https://doi.org/10.15951/j.tmgcxb.23070579.
SHAO J C, LI S G, ZHANG W X, et al. Effect of initial moisture content and compactness of sludge on strength of solidified soil[J/OL]. China Civil Engineering Journal, 1-13 (2023-12-08)[2024-08-02]. https://doi.org/10.15951/j.tmgcxb.23070579 (in Chinese).
[9] 刘丽. 软土固化中级配与水的作用机制及其调控[D]. 南京: 东南大学, 2022.
LIU L. Action mechanism and regulation of secondary mixing water in soft soil solidification[D]. Nanjing: Southeast University, 2022 (in Chinese).
[10] 冯志超, 朱伟, 张春雷, 等. 黏粒含量对固化淤泥力学性质的影响[J]. 岩石力学与工程学报, 2007, 26(增刊1): 3052-3057.
FENG Z C, ZHU W, ZHANG C L, et al. Influence of clay content on mechanical properties of solidified silt[J]. Chinese Journal of Rock Mechanics and Engineering, 2007, 26(supplement 1): 3052-3057 (in Chinese).
[11] 卞夏, 叶迎春, 刘凯, 等. 土性对工程泥浆固化强度影响规律及微观机理[J]. 地球学报, 2024, 45(1): 123-130.
BIAN X, YE Y C, LIU K, et al. The influence of soil properties on the stabilization strength of engineering slurry and its micro-mechanism[J]. Acta Geoscientica Sinica, 2024, 45(1): 123-130 (in Chinese).
[12] 黄继志. 水泥基矿物分散体系的微观作用力及流变性研究[D]. 广州: 华南理工大学, 2021.
HUANG J Z. Study on micro-force and rheology of cement-based mineral dispersion system[D]. Guangzhou: South China University of Technology, 2021 (in Chinese).
[13] WANG F T, LI K Q, LIU Y. Optimal water-cement ratio of cement-stabilized soil[J]. Construction and Building Materials, 2022, 320: 126211.
[14] GAO Y F, ZHAO G, MA P C, et al. Preliminary study on the water film at the soil-structure interface under cyclic loading[J]. Marine Georesources & Geotechnology, 2024: 1-5.
[15] 韩婷婷, 吴思麟, 吕一彦. 泥浆中水分形态对抗剪强度与流变性的影响[J]. 长江科学院院报, 2018, 35(2): 104-108.
HAN T T, WU S L, LÜ Y Y. Effect of water form on shear strength and rheologic performance of slurry[J]. Journal of Yangtze River Scientific Research Institute, 2018, 35(2): 104-108 (in Chinese).
[16] 胡湘锋. 黏土中水的形态对其工程性质的影响研究[D]. 广州: 华南理工大学, 2017.
HU X F. A study on the influence of water's state in clay on its Engineering properties[D]. Guangzhou: South China University of Technology, 2017 (in Chinese).
[17] LI H, WU A X, CHENG H Y. Generalized models of slump and spread in combination for higher precision in yield stress determination[J]. Cement and Concrete Research, 2022, 159: 106863.
[18] BARGHI KHEZERLOO A, DEHGHAN S M, SEPASDAR M. Using dune sand in controlled low-strength material for backfilling: field installation and numerical simulation[J]. Journal of Pipeline Systems Engineering and Practice, 2021, 12(1): 04020055.
[19] 尹振华, 张建明, 张虎, 等. 水泥改良冻土过程水分转化规律及对强度的影响[J]. 哈尔滨工业大学学报, 2021, 53(11): 136-144.
YIN Z H, ZHANG J M, ZHANG H, et al. Water transformation law of cement improved frozen soil and its effect on strength[J]. Journal of Harbin Institute of Technology, 2021, 53(11): 136-144 (in Chinese).
[20] 孙国文, 孙伟, 张云升, 等. 硅酸盐水泥水化产物体积分数定量计算[J]. 东南大学学报(自然科学版), 2011, 41(3): 606-610.
SUN G W, SUN W, ZHANG Y S, et al. Quantitative calculation on volume fraction of hydrated products in Portland cement[J]. Journal of Southeast University (Natural Science Edition), 2011, 41(3): 606-610 (in Chinese).
[21] SHEEN Y N, ZHANG L H, LE D H. Engineering properties of soil-based controlled low-strength materials as slag partially substitutes to Portland cement[J]. Construction and Building Materials, 2013, 48: 822-829.
[22] ZHANG R, XIAO Y P, GAO Q F, et al. Effect of adsorbed water on compression behavior of high liquid limit soils[J]. Journal of Central South University, 2023, 30(2): 530-541.
[23] GUO Q Q, CHEN Y H, XU J, et al. Investigation on mechanical parameters and microstructure of soil-based controlled low-strength materials with polycarboxylate superplasticizer[J]. Applied Sciences, 2024, 14(3): 1029.