Mechanical Properties and Crack Development Characteristics ofCement-Solidified Mud Soil under Dry-Wet-Freeze-Thaw Cycles

Abstract

Abstract: In order to study the effect of dry-wet-freeze-thaw (short as D-W-F-T) cycle on the properties of cement-solidified mud soil,triaxial shear tests,CT scan tests and SEM scan tests were carried out under different times of D-W-F-T cycle,and the mechanical characteristics and microstructure damage rules of cement-solidified mud soil were studied.The results show that the stress-strain curves of cement-solidified mud soil shows the strain hardening type.The internal friction angle and cohesion index gradually decrease with the increase of the number of D-W-F-T cycles,and the trend of exponential and linear decay are presented,respectively.The cracking evolution rules of the samples are quantitatively analyzed based on the binary CT scan images.It is found that the crack content of the sample increases exponentially with the increase of the number of D-W-F-T cycles.It is also observed by SEM scanning test that the D-W-F-T cycle causes the loss of cement-based materials in the samples and the decrease of compaction between particles,which is the microscopic mechanism that leads to the crack expansion and the mechanical properties weakening of cement-solidified mud soil.

Key words: cement-solidified mud soil, dry-wet-freeze-thaw cycle, triaxial shear test, mechanical property, crack development characteristic, micromorphologic

CLC Number:

TU525

TAO Pan. Mechanical Properties and Crack Development Characteristics ofCement-Solidified Mud Soil under Dry-Wet-Freeze-Thaw Cycles[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2021, 40(1): 34-40.

References

[1] 于伟,折学森.长江三角洲区域性软土路基沉降特性研究[J].安全与环境学报,2016,16(6):102-108.
YU W,ZHE X S.On the particular settlement features of the soft soil subgrade in the area of Yangtze River Delta[J].Journal of Safety and Environment,2016,16(6):102-108 (in Chinese).
[2] 秦世伟,陆小锋,张国军.水泥土搅拌法加固淤泥质黏土的试验研究[J].中外公路,2019,39(5):256-260.
QIN S W,LU X F,ZHANG G J.Experimental study on mucky clay strengthened by cement-soil mixed method[J].Journal of China and Foreign Highway,2019,39(5):256-260 (in Chinese).
[3] LIU J K,WANG T L,TIAN Y H.Experimental study of the dynamic properties of cement- and lime-modified clay soils subjected to freeze-thaw cycles[J].Cold Regions Science and Technology,2010,61(1):29-33.
[4] 慕焕东,邓亚虹,李荣建.干湿循环对地裂缝带黄土抗剪强度影响研究[J].工程地质学报,2018,26(5):1131-1138.
MU H D,DENG Y H,LI R J.Experimental study on strength characteristics of loess at ground fissures in Xi’an under action of dry and wet cycle[J].Journal of Engineering Geology,2018,26(5):1131-1138 (in Chinese).
[5] 周春梅,王琴华,张静波,等.干湿和冻融循环对压实黄土路用性能影响的试验研究[J].防灾减灾工程学报,2019,39(3):533-540.
ZHOU C M,WANG Q H,ZHANG J B,et al.Experimental study on the influence of dry-wet and freeze-thaw cycles on compacted loess road performance[J].Journal of Disaster Prevention and Mitigation Engineering,2019,39(3):533-540 (in Chinese).
[6] 赵春彦,黄启友,郎锋,等.单因素和多因素作用下的水泥土强度评估模型试验研究[J].铁道科学与工程学报,2018,15(11):2788-2795.
ZHAO C Y,HUANG Q Y,LANG F,et al.Experimental study on strength evaluation model of cement soil under single factor and multi factors[J].Journal of Railway Science and Engineering,2018,15(11):2788-2795 (in Chinese).
[7] 徐丽娜,牛雷,张颖,等.冻融循环作用下玄武岩纤维水泥土力学性质研究[J].工业建筑,2020,50(3):109-113.
XU L N,NIU L,ZHANG Y,et al.Effect of freeze-thaw cycling on the mechanical properties of fiber-reinforced cemented soil[J].Industrial Construction,2020,50(3):109-113 (in Chinese).
[8] 李芳菲,华渊,刘文化,等.干湿循环条件下水泥固化疏浚淤泥的物理力学特性[J].硅酸盐通报,2019,38(2):344-350.
LI F F,HUA Y,LIU W H,et al.Physico-mechanical characteristics of cement-solidified dredged sludge under drying and wetting cycle[J].Bulletin of the Chinese Ceramic Society,2019,38(2):344-350 (in Chinese).
[9] 陈四利,史建军,于涛,等.冻融循环对水泥土力学特性的影响[J].应用基础与工程科学学报,2014,22(2):343-349.
CHEN S L,SHI J J,YU T,et al.Effect of freezing-thawing cycle on the mechanical behaviors of cemented soil[J].Journal of Basic Science and Engineering,2014,22(2):343-349 (in Chinese).
[10] 汪洪星,柯睿,谈云志,等.固化淤泥土的干湿循环劣化特征[J].硅酸盐通报,2018,37(9):2704-2709.
WANG H X,KE R,TAN Y Z,et al.Deterioration characters of solidified/stabilized sediments by dry-wet circulations[J].Bulletin of the Chinese Ceramic Society,2018,37(9):2704-2709 (in Chinese).
[11] YAN C G,ZHANG Z Q,JING Y L.Characteristics of strength and pore distribution of lime-flyash loess under freeze-thaw cycles and dry-wet cycles[J].Arabian Journal of Geosciences,2017,10(24):1-10.
[12] 马军涛,王大广,陈浩,等.复杂环境下水泥改性生土砌块的导热系数及抗压强度分析[J].新型建筑材料,2019,46(12):113-116.
MA J T,WANG D G,CHEN H,et al.Analysis of thermal conductivity and compressive strength of cement modified raw soil blocks in complex environment[J].New Building Materials,2019,46(12):113-116 (in Chinese).
[13] LI L,SHAO W,LI Y D,et al.Effects of climatic factors on mechanical properties of cement and fiber reinforced clays[J].Geotechnical and Geological Engineering,2015,33(3):537-548.
[14] 许雷,鲁洋,薛洋,等.冻融循环下水泥改性膨胀土物理力学特性研究[J].长江科学院院报,2017,34(4):87-91+103.
XU L,LU Y,XUE Y,et al.Physico-mechanical properties of Cement-modified expansive soil under Freeze-thaw cycles[J].Journal of Yangtze River Scientific Research Institute,2017,34(4):87-91+103 (in Chinese).
[15] 安然,孔令伟,黎澄生,等.炎热多雨气候下花岗岩残积土的强度衰减与微结构损伤规律[J].岩石力学与工程学报,2020,39(9):1902-1911.
AN R,KONG L W,LI C S.Strength attenuation and microstructure damage of granite residual soil in hot and rainy climate[J].Journal of Rock Mechanics and Engineering,2020,39(9):1902-1911 (in Chinese).