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CHEN Yong-gui, LI Quan, JIA Ling-yan, YE Wei-min, CUI Yu-jun, CHEN Bao. Decay characteristics of swelling pressure of compacted bentonite under salinity gradient cycling[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(5): 872-879. DOI: 10.11779/CJGE201805012
Citation: CHEN Yong-gui, LI Quan, JIA Ling-yan, YE Wei-min, CUI Yu-jun, CHEN Bao. Decay characteristics of swelling pressure of compacted bentonite under salinity gradient cycling[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(5): 872-879. DOI: 10.11779/CJGE201805012

Decay characteristics of swelling pressure of compacted bentonite under salinity gradient cycling

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  • Revised Date: February 08, 2017
  • Published Date: May 24, 2018
  • During the long-term operation of a deep geological repository of high-level radioactive waste (HLW), the bentonite barrier is likely to experience the chemical cycling paths of groundwater with various chemical components. In this case, the swelling capacity of bentonite can be reduced to a certain degree. In this work, GMZ bentonite powder is densely compacted to a dry density of 1.7 g/cm3 to carry out the swelling pressure tests under the constant-volume conditions. The salinization-desalinization effect is investigated by cyclical infiltrations of NaCl solution and distilled water. Furthermore, the cation exchange effect is emphasized by sequential infiltrations of NaCl solution, distilled water and KCl solution. For both infiltration paths, the salt concentrations (0.5, 1 mol/L) are taken into account. The results show that the swelling pressure characteristics of GMZ bentonite depend on the ion species and salt concentration of infiltration solution as well as the number of chemical cycles. The salinization effect of salt solution results in the decrease in swelling pressure, while the infiltration of distilled water improves the swelling behaviors. The swelling pressure decreases with the salt concentration of infiltration solutions. The stable swelling pressure and its reduced degree gradually decrease against the number of chemical cycles. Under the infiltration of KCl solution, some of the montmorillonite is dissolved, which results in the significant decrease in swelling pressure. No swelling pressure will be measured for GMZ bentonite if the concentration of KCl solution is higher enough.
  • [1]
    LIU J, NERETNIEKS I. Physical and chemical stability of the bentonite buffer[R]. Stockholm: Royal Institute of Technology, 2006.
    [2]
    BERNER U R. Evolution of pore water chemistry during degradation of cement in a radioactive wasterepository environment[J]. Waste Management, 1992, 12(2/3): 201-219.
    [3]
    SÁNCHEZ L, CUEVAS J, RAM IREZ S, et al. Reaction kinetics of FEBEX bentonite in hyperalkalineconditions resembling the cement-bentonite interface[J]. Applied Clay Science, 2006, 33(2): 125-141.
    [4]
    NAKAYAMA S, SAKAMOTO Y, YAMAGUCHI T, et al. Dissolution of montmorillonite in compacted bentonite by highly alkaline aqueous solutions and diffusivity of hydroxide ions[J]. Applied Clay Science, 2004, 27(1/2) : 53-65.
    [5]
    THATCHER K E, BOND A E, ROBINSON P, et al. A new hydro-mechanical model for bentonite resaturation applied to the SEALEX experiments[J]. Environmental Earth Sciences, 2016, doi:10.1007/s12665- 016-5741-z.
    [6]
    BALLARINI E, GRAUPNER B, BAUER S. Thermal- hydraulic-mechanical behavior of bentonite and sand- bentonite materials as seal for a nuclear waste repository: numerical simulation of column experiments[J]. Applied Clay Science, 2017, 135: 289-299.
    [7]
    ZHAO Jing-bo, CHEN Liang, COLLIN F, et al. Numerical modeling of coupled thermal-hydro-mechanical behavior of GMZ bentonite in the China-Mock-up test[J]. Engineering Geology, 2016, 214: 116-126.
    [8]
    NASSER M S, ONAIZI Sagheer A, HUSSEIN I A, et al. Intercalation of ionic liquids into bentonite: Swelling and rheological behaviors[J]. Colloids and Surfaces A-Physicochemical and Engineering Aspects, 2016, 507: 141-151.
    [9]
    BENDITO E, PINTADO X. Monitoring of swelling pressure in bentonite[J]. Environmental Geotechnics-Journal, 2016, 3(5): 334-345.
    [10]
    OMAR M, SHANABLEH A, AL ZAYLAIE M. Modification of the swelling characteristics and phosphorus retention of bentonite clay using alum[J]. Soils and Foundations, 2016, 56(5): 861-868.
    [11]
    MASSAT L, CUISINIER O, BIHANNIC I, et al. Swelling pressure development and inter-aggregate porosity evolution upon hydration of a compacted swelling clay[J]. Applied Clay Science, 2016, 124: 197-210.
    [12]
    HERBERT H J, KASBOHM J, SPRENGER H, et al. Swelling pressures of MX-80 bentonite in solutions of different ionic strength[J]. Physics and Chemistry of the Earth, Parts A/B/C, 2008, 33: S327-S342.
    [13]
    CASTELLANOS E, VILLAR M V, ROMERO E, et al. Chemical impact on the hydro-mechanical behaviour of high-density FEBEX bentonite[J]. Physics and Chemistry of the Earth, Parts A/B/C, 2008, 33: S516-S526.
    [14]
    MUSSO G, ROMERO Morales E, GENS A, et al. The role of structure in the chemically induced deformations of FEBEX bentonite[J]. Applied Clay Science, 2003, 23(1/4): 229-237.
    [15]
    DI Maio C. Exposure of bentonite to salt solution: osmotic and mechanical effects[J]. Géotechnique, 1996, 46(4): 695-707.
    [16]
    GAJO A, LORET B. The mechanics of active clays circulated by salts, acids and bases[J]. Journal of the Mechanics & Physics of Solids, 2007, 55(8): 1762-1801.
    [17]
    YE W M, CUI Y J, QIAN L X, et al. An experimental study of the water transfer through confinedcompacted GMZ bentonite[J]. Engineering Geology, 2009, 108(3/4): 169-176.
    [18]
    MUSSO G, ROMERO Morales E, GENS A, et al. The role of structure in the chemically induced deformations of FEBEX bentonite[J]. Applied Clay Science, 2003, 23(1/4): 229-237.
    [19]
    郭永海, 杨天笑, 刘淑芬. 高放废物处置库甘肃北山预选区水文地质特征研究[J]. 铀矿地质, 2001, 17(3): 184-189. (GUO Yong-hai, YANG Tian-xiao, LIU Shu-fen. Hydrogeological characteristics of Beishan preselected area, Gansu province for China's high-level radioactive waste repository[J]. Uranium Geolog, 2001, 17(3): 184-189. (in Chinese))
    [20]
    于 响, 孙德安, 孙文静. 干湿循环下高庙子钙基膨润土持水和变形特性[J]. 岩土力学, 2015, 36(5): 1339-1346. (YU Xiang, SUN De-an, SUN Wen-jing. Water-retention and deformation characteristics of Gaomiaozi Ca-bentonite during wetting-drying cycles[J]. Rock and Soil Mechanics, 2015, 36(5): 1339-1346. (in Chinese))
    [21]
    秦 冰, 陈正汉, 刘月妙, 等. 高庙子膨润土GMZ001三向膨胀力特性研究[J]. 岩土工程学报, 2009, 31(5): 756-763. (QIN Bing, CHEN Zheng-han, LIU Yue-miao, et al. Characteristics of 3D swelling pressure of GMZ001 bentonite[J]. Chinese Journal of Geotechnical Engineering, 2009, 31(5): 756-763. (in Chinese))
    [22]
    刘月妙, 王 驹, 曹胜飞, 等. 中国高放废物地质处置缓冲材料大型试验台架和热-水-力-化学耦合性能研究[J]. 岩土力学, 2013, 34(10): 2756-2762. (LIU Yue-miao, WANG Ju, CAO Sheng-fei, et al. A large-scale THMC experiment of buffer material for geological disposal of high level radioactive waste in China[J]. Rock and Soil Mechanics, 2013, 34(10): 2756-2762. (in Chinese))
    [23]
    赖小玲, 叶为民, 刘 毅, 等. 高庙子膨润土膨胀力时效性试验研究[J]. 岩土工程学报, 2014, 36(3): 574-579. (LAI Xiao-ling, YE Wei-min, LIU Yi, et al. Experimental investigation on ageing effects on swelling pressure of unsaturated GMZ01 bentonite[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(3): 574-579. (in Chinese))
    [24]
    项国圣, 徐永福, 陈 涛, 等. 盐溶液中膨润土膨胀变形的分形模型[J]. 岩土力学, 2017, 38(1): 75-80. (XIANG Guo-sheng, XU Yong-fu, CHEN Tao, et al. Fractal model for swelling deformation of bentonite in salt solution[J]. Rock and Soil Mechanics, 2017, 38(1): 75-80. (in Chinese))
    [25]
    于海浩, 韦昌富, 颜荣涛, 等. 孔隙溶液浓度的变化对黏土强度的影响[J]. 岩土工程学报, 2015, 37(3): 564-569. (YU Hai-hao, WEI Chang-fu, YAN Rong-tao, et al. Effects of pore solution concentrations on shear strength of clay[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(3): 564-569. (in Chinese))
    [26]
    孙德安, 张 龙. 盐溶液饱和高庙子膨润土膨胀特性及预测[J]. 岩土力学, 2013, 34(10): 2790-2795. (SUN De-an, ZHANG Long. Swelling characteristics of Gaomiaozi bentonite saturated by salt solution and their prediction[J]. Rock and Soil Mechanics, 2013, 34(10): 2790-2795. (in Chinese))
    [27]
    陈永贵, 黄润秋, 朱春明, 等. 化学场对膨润土水-力特性影响研究进展[J]. 同济大学学报(自然科学版), 2014, 42(3): 398-405. (CHEN Yong-gui, HUANG Run-qiu, YE Wei-min, et al. Chemical environment effect on hydro- mechanical behaviour of compacted bentonite[J]. Journal of Tongji University (Natural Science), 2014, 42(3): 398-405. (in Chinese))
    [28]
    CHEN Y G, ZHU C M, YE W M, et al. Effects of solution concentration and vertical stress on the swelling behavior of compacted GMZ01 bentonite[J]. Applied Clay Science, 2016, 124-125: 11-20.
    [29]
    YE W M, HE Y, CHEN Y G, et al. Thermo-chemical effects on the smectite alteration of GMZ bentonite for deep geological repository[J]. Environmental Earth Sciences, 2016, 75: 905-915.
    [30]
    CHEN Y G, ZHU C M, YE W M, et al. Swelling pressure and hydraulic conductivity of compacted GMZ01bentonite under salinization-desalinization cycle conditions[J]. Applied Clay Science, 2015, 114: 54-460.
    [31]
    KAUFHOLD S, DOHRMANN R. Stability of bentonites in salt solutions/sodium chloride[J]. Applied Clay Science, 2009, 45(3): 171-177.
    [32]
    KAUFHOLD S, DOHRMANN R. Stability of bentonites in salt solutions II: potassium chloride solution-Initial step of illitization[J]. Applied Clay Science, 2010, 49(3) 98-107.
    [33]
    KAUFHOLD S, DOHRMANN R. Stability of bentonites in salt solutions III: calcium hydroxide[J]. Applied Clay Science, 2011, 51(1/2): 300-307.
    [34]
    PUSCH R. The buffer and backfill handbook part 1— definitions, basic relationships, and laboratory methods[R]. Stockholm: SKB Technical Report TR 02-20, 2002.
    [35]
    PUSCH R. The buffer and backfill handbook part 2 — materials and techniques[R]. Stockholm: SKB Technical Report TR 02-12, 2002.
    [36]
    ZHU C M, YE W M, CHEN Y G, et al. Influence of salt solutions on the swelling pressure and hydraulic conductivity of compacted GMZ01 bentonite[J]. Engineering Geology, 2013, 166(10): 74-80.
    [37]
    LUCKHAM P F, ROSSI S. The colloidal and rheological properties of bentonite suspensions[J]. Advances in Colloid and Interface Science, 1999, 82(1/3): 43-92.
    [38]
    SUZUKI S, PRAYONGPHAN S, ICHIKAWA Y, et al. In situ observations of the swelling of bentonite aggregates in NaCl solution[J]. Applied Clay Science, 2005, 29(2): 89-98.
    [39]
    SAVAGE D. The effects of high salinity groundwater on the performance of clay barriers[R]. Stockholm: Engineered Barrier System - Long-term Stability of Buffer and Backfill, Synthesis and Extended, SKI Report Sweden, 2004: 48-59.
    [40]
    BRADBURY M H, BAEYENS B. Porewater chemistry in compacted re-saturated MX-80 bentonite[J]. Journal of Contaminant Hydrology, 2003, 61(1): 329-338.
    [41]
    PUSCH R, YONG R N. Microstructure of smectite clays and engineering performance[M]. London and New York: Taylor & Francis US, 2006.

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