Scholarlink

<p>Sand-bentonite (SB) cutoff walls are commonly used as barriers in polluted areas. The embedded part of an SB wall in an aquitard is crucial for its performance. In this study, a centrifuge modeling test was carried out to investigate the effect of contact between the key and the aquitard on the migration behavior of contaminants within an SB cutoff wall. The centrifuge was accelerated to 100<i>g</i> (gravitational acceleration) and maintained in-flight for 36 h, equivalent to 41 years of transport time in the prototype. Results showed that the contaminant concentration within the SB wall was higher downstream than in the middle in the thickness direction, and deeper regions exhibited a greater concentration than shallower ones. This concentration distribution indicated that contaminants were transported along the interface between the SB wall and the aquitard, bypassing the base of the SB wall to reach the downstream aquifer rapidly. An improved numerical simulation considering preferential interface migration was performed, which agreed with the centrifuge test results. The simulation results indicated that preferential interface migration, as a defect, significantly accelerated the speed of contaminant migration, reducing the breakthrough time of the SB wall to 1/9 of that without preferential interface migration.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Centrifuge modeling of contaminant transport in keyed sand-bentonite cutoff walls

  • 期刊论文

  • 发表日期：

    2025年6月30日

查看全文
  • Bo Huang,
  • Linfeng Cao,
  • Jiachen Guo,
  • Chunrui Xu,
  • Yuchao Li

摘要

Sand-bentonite (SB) cutoff walls are commonly used as barriers in polluted areas. The embedded part of an SB wall in an aquitard is crucial for its performance. In this study, a centrifuge modeling test was carried out to investigate the effect of contact between the key and the aquitard on the migration behavior of contaminants within an SB cutoff wall. The centrifuge was accelerated to 100g (gravitational acceleration) and maintained in-flight for 36 h, equivalent to 41 years of transport time in the prototype. Results showed that the contaminant concentration within the SB wall was higher downstream than in the middle in the thickness direction, and deeper regions exhibited a greater concentration than shallower ones. This concentration distribution indicated that contaminants were transported along the interface between the SB wall and the aquitard, bypassing the base of the SB wall to reach the downstream aquifer rapidly. An improved numerical simulation considering preferential interface migration was performed, which agreed with the centrifuge test results. The simulation results indicated that preferential interface migration, as a defect, significantly accelerated the speed of contaminant migration, reducing the breakthrough time of the SB wall to 1/9 of that without preferential interface migration.