水泥固化土固化机理及抗冲刷特性

doi:10.11988/ckyyb.20230280

摘要/Abstract

摘要：

为了完善水泥固化土抗冲刷性能方面的研究,使水泥固化土在水下结构防护中得到应用,在砂土和黏土中分别掺入水泥和与液体固化剂,采用土体冲刷函数测定仪(EFA)对水泥固化土开展了抗冲刷性能试验。在分析砂土和黏土的固化作用机理基础上,研究了固化剂和固化时间对水泥固化土抗冲刷性能的影响。研究结果表明:水泥固化土的强度随固化时间的增长而增大,黏土的强度快速增长阶段要早于砂土;固化剂可以有效提高土体的起动切应力,同时可以大幅减小土体的冲刷速率,明显提高了土体的抗冲刷强度;起动切应力的增长速率随固化时间增长逐渐减缓,存在临界最大值。根据起动切应力的变化特征提出了水泥固化土起动切应力预测模型,经试验数据对比,该模型可以较好地预测水泥固化土的起动切应力随固化时间的变化规律。

关键词: 水泥固化土, 固化时间, 固化剂, 固化机理, 抗冲刷, 起动切应力

Abstract:

To enhance the erosion resistance of cement-solidified soil and facilitate its application in underwater structural protection, an investigation was conducted into the erosion resistance of cement-solidified soil through the addition of cement and a liquid curing agent to sand and clay. Erosion resistance tests were performed using the erosion function apparatus (EFA). The curing mechanisms was analyzed and the impact of curing agent and curing duration on the erosion resistance of cement-solidified soil was examined. The findings indicated that the strength of cement-solidified soil increased with longer curing times, with clay reaching its rapid strength development stage earlier than sand. Curing agent notably augmented the critical shear stress of the soil and significantly reduced erosion rates, thereby enhancing erosion resistance. Moreover, the rate of increase in critical shear stress gradually diminished with longer curing times until reaching a critical maximum value. Based on the observed variations in critical shear stress, a predictive model for the critical shear stress of cement-solidified soil was proposed. Experimental data comparisons validated the efficacy of the model in predicting critical shear stress variations with curing time.

Key words: cement-solidified soil, curing time, curing agent, curing mechanism, erosion resistance, critical shear stress

中图分类号:

TU442有粘合力(凝聚性)土与地基

王秋生, 修一兵, 齐云鹏, 邓启华, 李广耀. 水泥固化土固化机理及抗冲刷特性[J]. 院报, 2024, 41(8): 142-149.

WANG Qiu-sheng, XIU Yi-bing, QI Yun-peng, DENG Qi-hua, LI Guang-yao. Curing Mechanism and Erosion Resistance of Cement-solidified Soil[J]. Journal of Yangtze River Scientific Research Institute, 2024, 41(8): 142-149.

图/表 18

图1 砂土颗粒级配曲线

Fig.1 Particle grading curve of sand

表1 黏土的物理力学参数

Table 1 Physical and mechanical parameters of clay

土的类型	密度/(g·cm^-3)	液限/%	塑限/%	塑性指数
黏土	1.97	28.51	17.87	10.64

表2 固化剂成分及作用

Table 2 Components of curing agent and their effects

成分	作用
水	作为溶剂,提供液体环境
硅酸钠	可以在水中形成胶体,具有较高的粘聚性,能增加颗粒间的黏聚力
环氧树脂	环氧基化学活性相对活泼,固化交联生成网状结构,提高土体强度
二氧化硅	作为增韧剂,与土壤反应生成凝胶体填充土壤颗粒之间的孔隙

表3 试样配比设计

Table 3 Mix proportion of specimens

试样编号	水泥掺量/%	固化剂掺量/%	固化时间/h
S1	10	0.02	2
S2	10	0.02	3
S3	10	0.02	4
S4	10	0.02	5
S5	10	0.02	6
S6	10	0	2
S7	10	0	3
S8	10	0	4
S9	10	0	5
S10	10	0	6
CL1	10	0.02	2
CL2	10	0.02	3
CL3	10	0.02	4
CL4	10	0.02	5
CL5	10	0.02	6
CL6	10	0	2
CL7	10	0	3
CL8	10	0	4
CL9	10	0	5
CL10	10	0	6

图2 冲刷函数测定仪

Fig.2 Erosion function apparatus

图3 冲刷设备实物图

Fig.3 Photo of erosion equipment

图4 起动切应力的确定

Fig.4 Determination of critical shear stress

图5 固化剂固化砂土机理

Fig.5 Mechanism of curing agent curing sand

图6 固化剂固化黏土机理

Fig.6 Mechanism of curing agent curing clay

图7 砂土冲刷速率

Fig.7 Erosion rate of sand

图8 砂土起动切应力

Fig.8 Critical shear stress of sand

图9 黏土冲刷速率

Fig.9 Erosion rate of clay

图10 黏土起动切应力

Fig.10 Critical shear stress of clay

图11 砂土固化6 h冲刷速率对比

Fig.11 Comparison of erosion rate between unsolidified sand and sand solidified for six hours

图12 砂土起动切应力对比

Fig.12 Comparison of critical shear stress between unsolidified and solidified sand

图13 黏土固化6 h冲刷速率对比

Fig.13 Comparison of erosion rate between unsolidified clay and clay solidified for six hours

图14 黏土起动切应力对比

Fig.14 Comparison of critical shear stress between unsolidified and solidified clay

图15 起动切应力时间效应模型

Fig.15 Time effect model of critical shear stress

[1]	张洁雅, 杨帆, 曹家玮, 董晓强. 三元工业废渣协同水泥固化土的基本特性和机理分析[J]. 院报, 2024, 41(6): 122-129.
[2]	张志华, 杨晶, 汪倩, 黄金权, 邓灵敏, 许文盛. 基于生态无砂混凝土护岸的植物抗冲刷性能[J]. 院报, 2023, 40(8): 64-69.
[3]	李世汩, 陈文峰, 夏新星, 张航, 黄小龙, 徐杨帆, 胡南. 低碱性环保固化剂调理淤泥的板框压滤脱水试验研究[J]. 院报, 2023, 40(3): 46-51.
[4]	李永靖, 文成章, 王松, 程耀辉, 郝稳杰. CLFD-TS协同固化云母片岩强风化土性能试验研究[J]. 院报, 2023, 40(12): 88-95.
[5]	石娇, 张希栋, 甄志磊, 刘中华. 基于温度-应力耦合的冻土地区渠道衬砌防冻胀效果及适应性评价[J]. 院报, 2022, 39(3): 131-136.
[6]	徐鹏飞, 李泽莹, 王银梅, 董岩. 冻融循环对新型高分子材料SH固化黄土力学特性的影响试验研究[J]. 院报, 2021, 38(1): 137-141.
[7]	徐日庆, 文嘉毅, 董梅. 工业废料固化浅层淤泥质土研究[J]. 院报, 2020, 37(5): 85-91.
[8]	孙金伟, 张冠华, 杨贺菲, 张平仓. 坡耕地水土流失防治新材料W-OH固化剂对大豆和玉米生长特性的影响[J]. 院报, 2019, 36(3): 37-39.
[9]	李崇清,刘清秉,项伟,王菁莪,乔宇. SH固化剂复配无机材料加固黄土抗侵蚀试验研究[J]. 院报, 2018, 35(8): 90-94.
[10]	赵献辉,刘春原,左丽明,刘宇飞,庞云泽. 采空区充填新型浆液固化机理与影响因素研究[J]. 院报, 2018, 35(8): 72-77.
[11]	王凤华, 项伟, 袁悦锋. 离子土壤固化剂改性膨胀土冻融过程中水分迁移试验研究[J]. 院报, 2018, 35(7): 111-116.
[12]	崔勇涛, 刘文白. 固化剂固化疏浚土的渗透性与微观机理研究[J]. 院报, 2017, 34(5): 109-114.
[13]	罗丽, 刘文白, 王晓琳, 张恩槐. 固化疏浚泥室内渗透试验研究[J]. 院报, 2016, 33(3): 89-92.
[14]	雷雯,项伟. EN-1离子土壤固化剂对滑坡滑带土扰动样的改性机理研究[J]. 院报, 2014, 31(5): 47-51.
[15]	毛静民, 李色篆. PCSB固化建筑废渣的路面基层性能研究[J]. 院报, 2012, 29(8): 118-124.