Effects of boundary conditions on swelling behavior of buffer/backfill materials

被引：0
|
作者：
Li S.-J. [1 ]
Tang C.-S. [1 ]
Wang D.-W. [1 ]
Chen Z.-G. [1 ]
Shi B. [1 ]
机构：
[1] School of Earth Sciences and Engineering, Nanjing University, Nanjing
来源：
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | 2019年 / 41卷 / 04期
关键词：
Boundary condition; Buffer/backfill material; Multi-boundary condition dilatometer; Nuclear waste geological disposal; SEL curve; Swelling behavior;
D O I：
10.11779/CJGE201904013
中图分类号：
学科分类号：
摘要：
The swelling behavior of buffer/backfill materials in high-level radioactive waste (HLW) repository is one of the significant indices evaluating their buffer/backfill properties. Due to the limitations of test apparatus, most of the previous swelling tests are performed under two simple extreme boundary conditions of constant volume (CV) and constant mean stress (CMS), which can not effectively reflect the complex stress-strain state in the repository. A new set of multi-boundary conditions dilatometer is designed to carry out a series of swelling tests under CV, CMS and constant stiffness (CS) boundary conditions. Based on this custom-made test apparatus, the swelling behavior of GMZ buffer/backfill materials is tested under complex boundary conditions. The results indicate that the developed test apparatus has the advantages of simple operation and stable performance, which can effectively stimulate various boundary conditions. The boundary conditions have an important influence on the ultimate swelling indices of samples. More specifically, the relationship between various boundary conditions and the corresponding swelling pressure is CV > CS > CMS, and the relationship between these conditions and the corresponding swelling strain is CMS > CS > CV. The swelling equilibrium limit (SEL) curve can be used as a reference for predicting the ultimate swelling strain and pressure of soils during hydration under complex boundary conditions. The test results have certain reference significance for further understanding the swelling behavior and guiding the design of buffer/backfill materials in HLW repository. © 2019, Editorial Office of Chinese Journal of Geotechnical Engineering. All right reserved.
引用
收藏
页码：700 / 706
页数：6
相关论文
共 30 条
  • [1] Wang J., Geological disposal of high level radioactive waste in China: review and prospect, Uranium Geology, 25, 2, pp. 71-77, (2009)
  • [2] Tang C.-S., Cui Y.-J., Tang A.M., Et al., Stress and Strain Evolution of Remoulded COx Argillite during saturation, Chinese Journal of Geotechnical Engineering, 32, 8, pp. 1166-1171, (2010)
  • [3] Ye W.M., Chen Y.G., Chen B., Et al., Advances on the knowledge of the buffer/backfill properties of heavily-compacted GMZ bentonite, Engineering Geology, 116, 1, pp. 12-20, (2010)
  • [4] Ye W.-M., Pan H., Wang Q., Et al., Saturated permeability of highly compacted sand-bentonite mixtures under unconfined conditions, Chinese Journal of Geotechnical Engineering, 33, 6, pp. 869-874, (2011)
  • [5] Sun D.A., Cui H.B., Sun W.J., Swelling of compacted sand-bentonite mixtures, Applied Clay Science, 43, 3, pp. 485-492, (2009)
  • [6] Ye W.M., Cui Y.J., Qian L.X., Et al., An experimental study of the water transfer through confined compacted GMZ bentonite, Engineering Geology, 108, 3-4, pp. 169-176, (2009)
  • [7] Delage P., Howat M.D., Cui Y.J., The relationship between suction and swelling properties in a heavily compacted unsaturated clay, Engineering Geology, 50, 1-2, pp. 31-48, (1998)
  • [8] Wang Z.-J., Liu Q.-S., Experimental study of swelling characteristics of compacted sand-bentonite mixture, Rock and Soil Mechanics, 21, 4, pp. 331-334, (2000)
  • [9] Liu Y.-M., Xu G.-Q., Liu S.-F., Et al., Study on compactability and swelling property of buffer/backfill material for HLW repository, Uranium Geology, 17, 1, pp. 44-47, (2001)
  • [10] Ye W.-M., Schanz T., Qian L.-X., Et al., Characteristics of swelling pressure of densely compacted Gaomiaozi bentonite GMZ01, Chinese Journal of Rock Mechanics and Engineering, 26, pp. 3861-3865, (2007)
123