岩土工程学报2025，Vol.47Issue(7)：1527-1535,9.DOI:10.11779/CJGE20231186
不同级配GMZ膨润土颗粒混合物的热传导特性研究
Thermal conductivity of GMZ bentonite pellet mixtures with different grain-size distributions
摘要
Abstract
The bentonite pellet mixture has been proposed as a candidate backfilling material for technological gaps in deep geological repositories for disposal of high-level radioactive waste.Its thermal conductivity plays an important role in the safety assessment of the repository.In this study,a series of thermal conductivity tests are conducted on the GMZ bentonite pellet mixtures with different grain-size distributions.The results demonstrate that as the pellet size increases,the thermal conductivity of the mixtures firstly increases and then decreases for the specimens freely filled.However,the thermal conductivity monotonically decreases with the increase of the pellet size for the specimens packed at a given dry density.During the hydration process,the time-history curves of thermal conductivity for the pellet mixtures with different grain-size distributions can be approximately divided into a rapidly increasing stage and a stable stage.Meanwhile,the evolution and the stable time of thermal conductivity are both influenced by the particle composition.The bentonite pellets are swelled to fill the inter-pellet pores upon hydration,and the infiltration frontier gradually moves from the top/bottom part to the middle one,which is accompanied by a gradually structural transformation from a granular structure into a continuously homogeneous one.After approaching to the saturated state,the relationship between the thermal conductivity and the dry density for the bentonite pellet mixtures shows a good consistency to that of the compacted bentonite blocks.关键词
深地质处置/膨润土颗粒/导热系数/粒径级配Key words
deep geological disposal/bentonite pellet/thermal conductivity/grain-size distribution分类
土木建筑引用本文复制引用
张召,叶为民,李昱宛,贺勇,王琼,陈永贵..不同级配GMZ膨润土颗粒混合物的热传导特性研究[J].岩土工程学报,2025,47(7):1527-1535,9.基金项目
国家重点研发计划项目(2019YFC1509900) （2019YFC1509900）
国家自然科学基金项目(42207227) （42207227）
湖南省自然科学基金项目(2022JJ40586)This work was supported by the National Key Research and Development Program of China(Grant No.2019YFC1509900) （2022JJ40586）
the National Natural Science Foundation of China(Grant No.42207227) （Grant No.42207227）
the Natural Science Foundation of Hunan Province(Grant No.2022JJ40586). （Grant No.2022JJ40586）
