Mechanical properties and microstructure of solidified soil with low cement content

doi:10.3785/j.issn.1008-973X.2021.03.013

Journal of ZheJiang University (Engineering Science)

2021, Vol. 55

Issue (3): 530-538 DOI: 10.3785/j.issn.1008-973X.2021.03.013

Mechanical properties and microstructure of solidified soil with low cement content

Hai-chao SUN1,2(

),Wen-jun WANG2,3,*(

),Dao-sheng LING1,2

1. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Institute of Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China
2. School of Civil Engineering and Architecture, NingboTech University, Ningbo 315100, China
3. Ningbo Research Institute, Zhejiang University, Ningbo 315100, China

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Abstract

Unconfined compressive strength tests, one-dimensional compression tests and scanning electron microscope tests of solidified tideland sludge with different mass fractions of initial water and different cement contents were carried out. The mechanical properties and the microstructure characteristics of the solidified soil with low cement content and the differences from the solidified soil with conventional cement content were analyzed. Results show that the linear relationships between the boundary cement content, the minimum cement content and the initial moisture content of the sludg are obvious. Compared with the solidified soil with conventional cement content, the strength of the solidified soil with low cement content increases more slowly and its compressibility decreases less. The consolidation yield stress increases with the increase of cement content, and there is a nonlinear relationship between the consolidation yield stress and cement content in the low content range. There are great differences in the pore morphology and pore arrangement of the solidified soil with low cement content before and after yielding. When the consolidation pressure is less than the consolidation yield stress, pore orientation is not obvious, and pore arrangement is disordered. When the consolidation pressure is more than the consolidation yield stress, pore shape becomes smooth, the complexity decreases, and pore arrangement tends to be orderly with the increase of the load.

Key words： cement-solidified soil mechanical property boundary cement content consolidation yield stress microstructure characteristics

Received: 07 February 2020 Published: 25 April 2021

CLC:

TU 411

Fund: 浙江省自然科学基金资助项目（LY19E080013）；国家重点研发计划资助项目（2016YFC0800200）

Corresponding Authors: Wen-jun WANG E-mail: 616547136@qq.com;wwjcumt@nit.zju.edu.cn

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Cite this article:

Hai-chao SUN,Wen-jun WANG,Dao-sheng LING. Mechanical properties and microstructure of solidified soil with low cement content. Journal of ZheJiang University (Engineering Science), 2021, 55(3): 530-538.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2021.03.013 OR http://www.zjujournals.com/eng/Y2021/V55/I3/530

低掺量水泥固化土的力学特性及微观结构

针对某滩涂淤泥，开展不同淤泥初始水的质量分数、不同水泥掺量的固化土无侧限抗压强度试验、一维压缩试验以及扫描电镜试验，研究低掺量水泥固化土的力学特性与微观结构特征，探讨其与常规掺量固化土的差异. 结果表明：分界水泥掺量、最低水泥掺量与淤泥初始水的质量分数的线性关系明显；与常规掺量固化土相比，低掺量固化土的强度增长明显较慢，压缩性降低较少；固结屈服应力随水泥掺量增加而增大，在较低掺量区，固结屈服应力与水泥掺量具有非线性关系；低掺量固化土屈服前、后的孔隙形态特征以及孔隙排列特征差异较大，当固结压力小于固结屈服应力时，孔隙未呈现出明显的定向性且排列较为混乱，当固结压力大于固结屈服应力时，随着荷载的增加，孔隙形状变得圆滑，复杂程度降低，孔隙排列逐渐趋向于有序.

关键词： 水泥固化土, 力学特性, 分界水泥掺量, 固结屈服应力, 微观结构特征

Tab.1 Main physical property index of tideland sludge

Tab.2 Test scheme of solidified soil

Fig.1 Variation of unconfined compressive strength with cement content

Tab.3 Strength growth of solidified soil with 1% increase of cement content

Fig.2 Fitting curve of boundary cement content and ratio of mass fraction of initial water to liquid limit

Fig.3 Fitting curve of minimum cement content and mass fraction of initial water

Fig.4 Normalized curve of unconfined compressive strength and water-cement ratio

Fig.5 SEM images of solidified soil with different cement content（10 000 times）

Fig.6 Cumulative distribution curves of pores

Fig.7 Proportion of pores within a certain scale

Fig.8 One-dimensional compression test curves

Tab.4 Compressibility index of solidified soil before and after yielding

Fig.9 Double logarithmic compression curves

Fig.10 Variation of consolidation yield stress with cement content

Fig.11 Variation of average pore area with consolidation pressure

Fig.12 Variation of area probability distribution index with consolidation pressure

Fig.13 Variation of pore probability entropy with consolidation pressure

Fig.14 Rose diagrams of vertical section of solidified soil samples under different consolidation pressures

Fig.15 Variation of average pore shape factor with consolidation pressure


[1]	袁飞飞. 高含水率滩涂淤泥固化土的工程特性研究[D]. 杭州: 浙江大学, 2017. YUAN Fei-fei. The Study on engineering properties of solidified tidal silt with high water content [D]. Hangzhou: Zhejiang University, 2017.

[2]	HORPIBULSUK S, BERGADO D T, LORENZO G A Compressibility of cement-admixed clays at high water content[J]. Géotechinique, 2004, 54 (2): 151- 154

[3]	HORPIBULSUK S, RACHAN R, SUDDEEPONG A Assessment of strength development in blended cement admixed Bangkok clay[J]. Construction and Building Materials, 2011, 25 (4): 1521- 1531 doi: 10.1016/j.conbuildmat.2010.08.006

[4]	KAMRUZZAMAN A H M, CHEW S H, LEE F H Structuration and destructuration behavior of cement-treated Singapore marine clay[J]. Journal Geotechnical and Geoenvironmental Engineering, 2009, 135 (4): 573- 589 doi: 10.1061/(ASCE)1090-0241(2009)135:4(573)

[5]	KITAZUME M, HAYANO K Strength properties and variance of cement-treated ground using the pneumatic ?ow mixing method[J]. Ground Improvement, 2007, 11 (1): 21- 26 doi: 10.1680/grim.2007.11.1.21

[6]	ZHANG R J, SANTOSO A M, TAN T S, et al Strength of high water-content marine clay stabilized by low amount of cement[J]. Journal Geotechnical and Geoenvironmental Engineering, 2013, 139 (12): 2170- 2181 doi: 10.1061/(ASCE)GT.1943-5606.0000951

[7]	章荣军, 郑少辉, 郑俊杰低掺量水泥固化高含水率黏土强度特性研究[J]. 华中科技大学学报: 自然科学版, 2015, 43 (10): 101- 106 ZHANG Rong-jun, ZHENG Shao-hui, ZHENG Jun-jie Experimental study on strength behavior of high water content clay stabilized by low amount cement[J]. Journal of Huazhong University of Science and Technology: Natural Science Edition, 2015, 43 (10): 101- 106

[8]	郑少辉, 赖汉江, 章荣军, 等不同水灰比水泥固化黏土的强度特性试验研究[J]. 地下空间与工程学报, 2014, 10 (6): 1281- 1284 ZHENG Shao-hui, LAI Han-jiang, ZHANG Rong-jun, et al Experimental research on strength characteristics of cement: stabilized clay with different water-cement ratio[J]. Chinese Journal of Underground Space and Engineering, 2014, 10 (6): 1281- 1284

[9]	LIU S Y, ZHANG D W, LIU Z B, et al Assessment of unconfined compressive strength of cement stabilized marine clay[J]. Marine Georesources and Geotechnology, 2008, 26 (1): 19- 35 doi: 10.1080/10641190801937916

[10]	朱伟, 张春雷, 高玉峰, 等海洋疏浚泥固化处理土基本力学性质研究[J]. 浙江大学学报: 工学版, 2005, 39 (10): 1561- 1565 ZHU Wei, ZHANG Chun-lei, GAO Yu-feng, et al Fundamental mechanical properties of solidified dredged marine sediment[J]. Journal of Zhejiang University: Engineering Science, 2005, 39 (10): 1561- 1565

[11]	储诚富, 洪振舜, 刘松玉, 等用似水灰比对水泥土无侧限抗压强度的预测[J]. 岩土力学, 2005, 26 (4): 645- 649 CHU Cheng-fu, HONG Zhen-shun, LIU Song-yu, et al Prediction of unconfined compressive strength of cemented soils with quasi-water-cement ratio[J]. Rock and Soil Mechanics, 2005, 26 (4): 645- 649 doi: 10.3969/j.issn.1000-7598.2005.04.030

[12]	丁建文, 吴学春, 李辉, 等疏浚淤泥固化土的压缩特性与结构屈服应力[J]. 工程地质学报, 2012, 20 (4): 627- 632 DING Jian-wen, WU Xue-chun, LI Hui, et al Compression properties and structure yield stress for solidified soil composing of dredged clays[J]. Journal of Engineering Geology, 2012, 20 (4): 627- 632 doi: 10.3969/j.issn.1004-9665.2012.04.021

[13]	黄英豪, 朱伟, 周宣兆, 等固化淤泥压缩特性的试验研究[J]. 岩土力学, 2012, 33 (2): 2924- 2928 HUANG Ying-hao, ZHU Wei, ZHOU Xuan-zhao, et al Experimental study of compressibility behavior of solidified dredged material[J]. Rock and Soil Mechanics, 2012, 33 (2): 2924- 2928

[14]	KANG G, TSUCHIDA T, ATHAPATHTHU A M R G Strength mobilization of cement-treated dredged clay during the early stages of curing[J]. Soils and Foundations, 2015, 55 (2): 375- 392 doi: 10.1016/j.sandf.2015.02.012

[15]	JIANG H M, LIU W B Experimental study on deformability and shear strength of solidified dredged soil[J]. Applied Mechanics and Materails, 2013, 295–298: 1755- 1762 doi: 10.4028/www.scientific.net/AMM.295-298.1755

[16]	WANG D X, ABRIAK N E Compressibility behavior of Dunkirk structured and reconstituted marine soils[J]. Marine Georesources Geotechnology, 2015, 33 (5): 419- 428 doi: 10.1080/1064119X.2014.950798

[17]	WANG D X, ZENTAR R, ABRIAK N E Interpretation of compression behavior of structured and remolded marine soils[J]. Journal Materials in Civil Engineering, 2016, 28 (6): 04016005 doi: 10.1061/(ASCE)MT.1943-5533.0001503

[18]	黄英豪, 朱伟, 董婵, 等固化淤泥结构性力学特性的试验研究[J]. 水利学报, 2014, 45 (Suppl.2): 130- 136 HUANG Ying-hao, ZHU Wei, DONG Chan, et al Experimental study on structural behaviour of solidified dredged material[J]. Journal of Hydraulic Engineering, 2014, 45 (Suppl.2): 130- 136

[19]	CHIU C F, ZHU W, ZHANG C L Yielding and shear behavior of cement-treated dredged materials[J]. Engineering Geology, 2009, 103 (1/2): 1- 12 doi: 10.1016/j.enggeo.2008.07.007

[20]	周建, 邓以亮, 曹洋, 等杭州饱和软土固结过程微观结构试验研究[J]. 中南大学学报: 自然科学版, 2014, 45 (6): 1998- 2005 ZHOU Jian, DENG Yi-liang, CAO Yang, et al Experimental study on microstructure of Hangzhou saturated soft soil during consolidation process[J]. Journal of Central South University: Science and Technology, 2014, 45 (6): 1998- 2005

[21]	GB/T50123—2019. 土工试验方法标准[S]. 北京: 中华人民共和国住房和城乡建设部, 2019.

[22]	丁建文, 刘铁平, 曹玉鹏, 等高含水率疏浚淤泥固化土的抗压试验与强度预测[J]. 岩土工程学报, 2013, 35 (Suppl.2): 55- 60 DING Jian-wen, LIU Tie-ping, CAO Yu-peng, et al Unconfined compression tests and strength prediction method for solidified soils of dredged clays with high water content[J]. Chinese Journal of Geotechnical Engineering, 2013, 35 (Suppl.2): 55- 60

[23]	汤怡新, 刘汉龙, 朱伟水泥固化土工程特性试验研究[J]. 岩土工程学报, 2000, 22 (5): 549- 554 TANG Yi-xin, LIU Han-long, ZHU Wei Study on engineering properties of cement-stabilized soil[J]. Chinese Journal of Geotechnical Engineering, 2000, 22 (5): 549- 554 doi: 10.3321/j.issn:1000-4548.2000.05.008

[24]	LIU C, SHI B, ZHOU J Quantification and characterization of microporosity by image processing, geometric measurement and statistical methods: application on SEM images of clay materials[J]. Applied Clay Science, 2011, 54 (1): 97- 106 doi: 10.1016/j.clay.2011.07.022

[25]	BUTTERFIELD R A natural compression law for soils[J]. Géotechinique, 1979, 29 (4): 469- 480

[26]	汤强, 刘春, 顾颖凡, 等土体SEM图像微观结构的识别和统计方法[J]. 桂林理工大学学报, 2017, 37 (3): 547- 552 TANG Qiang, LIU Chun, GU Ying-fan, et al Microstructure identification and statistical method of the soil SEM image[J]. Journal of Guilin University of Technology, 2017, 37 (3): 547- 552

[27]	施斌黏性土微观结构定向性的定量研究[J]. 地质学报, 1997, 71 (1): 36- 44 SHI Bin Quantitative research of clay microstructure orientation characteristics for clay[J]. Geological Journal, 1997, 71 (1): 36- 44

[28]	孟庆山, 杨超, 许孝祖, 等动力排水固结前后软土微观结构分析[J]. 岩土力学, 2008, 29 (7): 1759- 1763 MENG Qing-shan, YANG Chao, XU Xiao-zu, et al Analysis of microstructure of soft clay before and after its improvement with dynamic consolidation by drainage[J]. Rock and Soil Mechanics, 2008, 29 (7): 1759- 1763 doi: 10.3969/j.issn.1000-7598.2008.07.006

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